Systems, devices, and methods for detecting, measuring, and / or monitoring fetal heart rate and methods for using same

Abstract

Fetal electrocardiogram (ECG) measurement devices and systems may be configured to be inserted vaginally so that ECG lead(s) thereof may be in electrical communication with skin of a fetus in utero. A portion of the fetal ECG devices holding one or more ECG lead(s) may be configured for placement within a pregnant mammal's uterus outside and / or inside the amniotic sac. Optionally, the fetal ECG devices may include one or more stabilization devices configured to hold ECG leads of the ECG devices against fetal skin and / or in electrical communication with fetal skin by, for example, occupying space between the fetus and amniotic sac and / or uterus and / or wedging between the fetus and amniotic sac and / or uterus.

Description

SYSTEMS, DEVICES, AND METHODS FOR DETECTING, MEASURING, AND / OR MONITORING FETAL HEART RATE AND METHODS FOR USING SAMERelated Application

[0001] This application is an INTERNATIONAL (PCT) application of, and claims priority to, United States Provisional Patent Application Number: 63 / 618,005, filed on 05 January 2024 and entitled “SYSTEMS, DEVICES, AND METHODS FOR DETECTING, MEASURING, AND / OR MONITORING FETAL HEARTRATE AND METHODS FOR USING SAME,” which is incorporated herein by reference.Technical Field

[0002] The present invention is in the field of medical devices and, more particularly, in the field of fetal wellness, fetal heart rate monitoring, and fetal electrocardiograms.Background

[0003] Electronic fetal heart rate monitoring is performed on over 90% of laboring women in the developed world through non-invasive, transabdominal Doppler ultrasound. This technique provides the fetal heart rate but not fetal ECGs. When monitoring a fetus, particularly during labor and delivery, fetal heart rate and fetal heart rate variability is measured over time in conjunction with uterine contractions to identify fetuses that are not tolerating the birthing process well due to a lack of oxygen transfer from the placenta during uterine contractions. These fetuses are at risk for developing hypoxic ischemic encephalopathy and may require an intervention to expedite birth, such as a C-section or instrumented vaginal delivery with the use of forceps and / or an episiotomy.

[0004] When the Doppler ultrasound fails to provide a reliable fetal heart rate signal, the clinician may decide to directly place a fetal scalp electrode into the ferrtus’s head (via screwing a tip of the fetal scalp electrode into the fetus’s skin) within the birth canal to reliably measure the fetal heart rate signal. It has been reported that about 10% of births in a community hospital will receive a fetal scalp electrode and 20% of births in an academic medical center. Fetal scalp electrodes are not risk-free as they are screwed into the fetus's head. There are bleeding and infection risks as well as the risk of a retained product associated with fetal scalp electrodes. In 2023,there was an FDA recall of fetal scalp electrodes because the tips were breaking off and requiring surgery for removal from the newborn baby.

[0005] Furthermore, use of fetal scalp electrodes that puncture fetal skin is contraindicated when there is an active infection in the vaginal birth canal during labor because there is a greater risk of infection via the puncture wound. For example, there have been cases reported of vaginal flora seeding the fetal brain during placement of a scalp electrode and precipitating an infection in the newborn baby. This risk is further compounded by the fact that blood / brain barrier of the fetus has not fully developed and, consequently, the risk of a newborn developing a brain infection or meningitis during the first month of life is increased via these infections.Summary

[0006] The fetal electrocardiogram (ECG) measurement devices and systems disclosed herein may be configured to measure, obtain, and / or generate fetal ECG data and / or fetal heart rate data. The fetal ECG devices and systems may include one or more ECG lead(s) configured to be in electrical communication with skin (e.g., cheek, back, head, arm, chest, etc.) of a fetus in utero (e.g., prior to the onset of labor, during the first stage of labor, and / or at the onset of the second stage of labor) and a positioning extension configured to enable positioning the ECG lead(s) onto the skin of the fetus and / or in electrical contact with the fetal skin via, for example, positioning of the ECG lead(s) between the uterine wall and amniotic sac of a mammal pregnant with the fetus. The ECG lead(s) may be communicatively coupled to at least one of a processor and a receiver that may be in communication with the processor and may be configured provide ECG measurements (e.g., raw ECG data) to the processor and / or receiver.

[0007] For embodiments including two or more ECG leads, the ECG leads may be positioned within a housing that includes one or more electrical and / or mechanical barriers configured to electrically isolate the ECG leads from one another.

[0008] The mechanical barrier may be configured as an extension that extends from and / or into a surface of the housing proximate to one or more of the ECG leads. In some embodiments, the mechanical barrier may be configured to control a magnitude of impedance induced by amniotic fluid across two or more of the ECG leads.

[0009] Additionally, or alternatively, the fetal ECG measurement devices disclosed herein may include one or more electrically-isolating element(s) sized, configured, and / or positioned to electrically insulate a first ECG lead from a second ECG lead. In some embodiments, the electrically-isolating element(s) may be configured as an extension that extends from a surface of the device and surrounds the first ECG lead so that a volume of amniotic fluid may be contained within the electrically-isolating element, wherein the volume of amniotic fluid contained within the electrically- isolating element may be electrically isolated from the second ECG lead.

[0010] The positioning extension may be configured as, for example, a semirigid wand, handle, or other device configured to enable a clinician to insert the device into, and through, the vagina and cervix to be proximate to the fetus. The positioning extension may include a communication interface (e.g., cord, wireless transceiver, etc.) configured to electrically and / or communicatively couple to the ECG lead(s) and the processor and / or receiver. At times, the positioning extension may include one or more reference electrode configured to contact / electrically couple with maternal tissue (e.g., cervix, vagina, etc.).

[0011] In some embodiments, the ECG lead may be positioned within a first, or active, side housing (e.g., sit proud of the housing) and a second side (e.g., opposed to the first side) may include one or more stabilization devices configured to hold the ECG lead(s) in contact with fetal skin. The stabilization device may be configured to occupy space between the fetus and internal uterine wall and assist with maintaining contact between the fetal skin and the ECG lead(s). In some embodiments, the stabilization device may be configured to face an internal uterine wall when in situ. At times, a size and / or volume of the stabilization device may be adjustable via, for example, inflation, deflation, and / or expansion / contraction of a material included in the stabilization device. When the stabilization device is inflatable, the fetal ECG measurement device may include an inflation line resident, for example, in the positioning extension. The inflation line may be in communication with the stabilization device and configured to communicate fluid to and / or from the stabilization device may be inflatable, thereby adjusting a size and / or volume of the stabilization device. At times, a degree, or amount, of inflation of the stabilization device may be responsive to back pressure exerted on the inflation line and / or to ECG data. Additionally, or alternatively, the stabilization device comprises a materialthat expands into space between the fetus and internal uterine wall when exposed to amniotic fluid.

[0012] Additionally, or alternatively, the fetal ECG measurement device may include an extension positioned on a surface of the housing opposing the active side of the housing. The extension may be configured to assist with positioning and / or maintaining a position the ECG measurement device proximate to the fetal skin. Additionally, or alternatively, the fetal ECG measurement devices disclosed herein may include an engagement mechanism configured to hold the fetal ECG measurement device against the fetal skin during use.

[0013] In many embodiments, the fetal ECG measurement devices disclosed herein may include one or more reference electrode(s) positioned to contact and / or electrically couple with maternal tissue (e.g., on a second side of the housing facing away from the ECG lead(s))

[0014] In some embodiments, the fetal ECG measurement devices disclosed herein may include a temperature sensor configured to measure a temperature of the fetus and / or a mammal who is pregnant with the fetus. Additionally, or alternatively, the fetal ECG measurement devices disclosed herein may include one or more markers configured to be opaque (e.g., echo opaque) to an imaging technology.

[0015] Methods of using the fetal ECG measurement devices and systems disclosed herein include, but are not limited to, using the fetal ECG measurement devices and systems and / or data generated using the fetal ECG measurement devices and systems to obtain fetal ECG measurement data, generate a fetal ECG graph or measurement, and / or determine fetal heart rate data.

[0016] At times, when the methods disclosed herein are executed by a processor and / or computer, data from an ECG lead in electrical communication with fetal skin positioned within a pregnant mammal’s uterus may be received and used to generate an ECG for the fetus, which may be provided to a user via a display device and / or printout. At times, generation of the fetal ECG may include receiving data from a reference electrode lead not in electrical communication with the fetus and using data from the reference electrode to generate a differential ECG.

[0017] Additionally, or alternatively, in some embodiments, a level of impedance and / or bioimpedance indicated by the received data may be received and / or analyzed to, for example, determine whether or not an ECG lead isfunctioning properly and / or is electrically coupled to the fetal skin and, when it isn’t, an error indication may be provided to a display device responsively to an indication that the level of impedance may be outside (e.g., above) a threshold value. Additionally, or alternatively, in some embodiments, the ECG data (e.g., raw, differential, and / or conditioned ECG data) may be analyzed to determine a level of shunt between ECG leads that may be indicated by the ECG data and, when the level of shunt is outside a range of values (e.g., acceptable values), an error indication may be provided to a display device. Additionally, or alternatively, in some embodiments, the ECG data (e.g., raw, differential, and / or conditioned ECG data) may be analyzed to, for example, determine whether there is an error condition present within the data and, if so, a correction and / or calibration may be applied to the data to reduce an impact of the error condition within the data.

[0018] Additionally, or alternatively, in some embodiments, temperature data from a temperature sensor positioned in a uterus of a mammal who may be pregnant with the fetus may be received and provided to the display device to, for example, monitor for infection.

[0019] In some embodiments, the systems, devices, and / or methods disclosed herein may be analog equipment and / or methods and, in these embodiments, the ECG data e.g., raw, differential, and / or conditioned ECG data) may be received by a printout device (e.g., a strip recorder) configured to generate a printout of the ECG data.Brief Description of the Figures

[0020] The present invention is illustrated by way of example, and not limitation, in the figures of the accompanying drawings in which:

[0021] FIG. 1 is a block diagram of an exemplary system for detecting, measuring, and / or monitoring fetal heart rate, consistent with some embodiments of the present invention;

[0022] FIG. 2A provides a schematic diagram of a top plan view of a first exemplary system that includes a first fetal ECG measurement device and an optional external reference electrode , in accordance with some embodiments disclosed herein;

[0023] FIG. 2B1 provides a schematic diagram of a top plan view of a second exemplary fetal ECG measurement device, in accordance with some embodiments disclosed herein;

[0024] FIG. 2B2 provides a schematic diagram of a cross section the second exemplary fetal ECG measurement device of FIG. 2B1 when positioned in utero proximate to fetal skin, in accordance with some embodiments disclosed herein;

[0025] FIG. 2C provides a schematic diagram of a top plan view of a third exemplary fetal ECG measurement device, in accordance with some embodiments disclosed herein;

[0026] FIG. 2D1 provides a schematic diagram of a top plan view of a fourth exemplary fetal ECG measurement device, in accordance with some embodiments disclosed herein;

[0027] FIG. 2D2 provides a schematic diagram of a vertical cross section of a housing of the fourth exemplary fetal ECG measurement device of FIG. 2D1 , in accordance with some embodiments disclosed herein;

[0028] FIG. 2D3 provides a schematic diagram of a horizontal cross section of the fourth exemplary fetal ECG measurement device of FIG. 2D1when positioned in utero proximate to fetal skin 290, in accordance with some embodiments disclosed herein;

[0029] FIG. 2E1 provides a schematic diagram of a top plan view of a fifth exemplary fetal ECG measurement device, in accordance with some embodiments disclosed herein;

[0030] FIG. 2E2 provides a schematic diagram of a cross section view of a housing of the fifth exemplary fetal ECG measurement device of FIG. 2E1 , in accordance with some embodiments disclosed herein;

[0031] FIG. 2E3 provides a schematic diagram of a cross section view of a housing of the fifth exemplary fetal ECG measurement device of FIG. 2E1 showing an air gap, in accordance with some embodiments disclosed herein;

[0032] FIG. 2F provides a schematic diagram of a side view of the fetal ECG measurement device of FIGs. 2A, 2B1 , 2C, 2D1 , or 2E1 with a stabilization device, in accordance with some embodiments disclosed herein;

[0033] FIG. 2G provides a schematic diagram of a side view of the fetal ECG measurement device of FIGs. 2A, 2B1 , 2C, 2D1 , or 2E1 with an extension, in accordance with some embodiments disclosed herein;

[0034] FIG. 3A provides a schematic diagram of a diagram of a top view of an exemplary fetal ECG measurement device configured for placement on a fetal head, in accordance with some embodiments disclosed herein;

[0035] FIG. 3B provides a schematic diagram of a diagram of a top view of another exemplary fetal ECG measurement device configured for placement on a fetal head, in accordance with some embodiments disclosed herein;

[0036] FIG. 3C provides a schematic diagram of a diagram of a top view of yet another exemplary fetal ECG measurement device configured for placement on a fetal head, in accordance with some embodiments disclosed herein;

[0037] FIG. 3D provides a schematic diagram of a cross section view of the exemplary fetal ECG measurement device of FIG. 3A, 3B, or 3C, in accordance with some embodiments disclosed herein; and

[0038] FIG. 4 provides a flowchart illustrating a process 400 for generating an electrocardiogram (ECG) for a fetus in utero, in accordance with some embodiments disclosed herein.

[0039] Throughout the drawings, the same reference numerals, and characters, unless otherwise stated, are used to denote like features, elements, components, or portions of the illustrated embodiments. Moreover, while the subject invention will now be described in detail with reference to the drawings, the description is done in connection with the illustrative embodiments. It is intended that changes and modifications can be made to the described embodiments without departing from the true scope and spirit of the subject invention as defined by the appended claims.Description

[0040] Direct measurement of fetal electrocardiography (ECG) information via contact and / or electrical coupling with skin of a fetus via a fetal ECG measurement device is a highly accurate way to measure and / or determine fetal heart rate. The fetal ECG measurement devices and systems disclosed herein may include one or more components (e.g., leads or electrodes collectively referred to herein as “ECG leads”) configured to sense electrical changes triggering and / or corresponding to a fetal heartbeat while the fetus is in utero and at times, may be used within the uterus of a mammal pregnant with the fetus. The ECG leads may comprise gel, stainless steel, brass, gold, carbon, platinum, silver, and / or a non-polarizable material such as silver / silver chloride (Ag / AgCI), and / or combinations thereof and may be configuredand / or selected to, for example, provide an improved DC offset and / or lower noise in a signal provided by the ECG leads.

[0041] The ECG lead(s) may be configured to directly contact fetal skin and / or be electrically coupled to fetal skin via a conductive fluid (e.g., amniotic fluid) by, for example, insertion into the uterus via a vaginal route so that one or more leads of the fetal ECG measurement device may contact fetal skin (e.g., cheek or back). In some embodiments, one or more of the ECG leads disclosed herein may include one or more features configured and arranged to engage with skin (e.g., scalp, back, and / or cheek) while the fetus is positioned within the uterus to, for example, improve physical contact between the fetus and the ECG lead, which may improve electrical communication between the fetus and the one or more ECG lead(s) and / or reduce amniotic and / or electrical shunting. Additionally, or alternatively, the fetal ECG measurement devices disclosed herein may be electrically coupled to fetal skin via a conductive fluid, such as amniotic fluid, via, for example, placement on the amniotic sac, which may be accomplished by, for example, positioning a fetal ECG measurement device between a uterus and the amniotic sac of a mammal pregnant with the fetus and / or contacting the amniotic sac via the internal cervical os of the pregnant mammal (e.g., inserted through the cervix to contact an unruptured amniotic sac). Additionally, or alternatively, the fetal ECG measurement devices disclosed herein may be configured to directly contact skin of a fetus’ head via a dilated (e.g., 1- 10cm) cervix and / or when positioned at, for example, -1 to +3 station.

[0042] In some embodiments, an outer surface of the fetal ECG measurement devices disclosed herein may be covered and / or treated with a lubricious coating to, for example, facilitate movement of outer surface of a fetal ECG measurement device along an interior wall of the uterus, an interface between an inner wall of the uterus and an amniotic sac, cervix, and / or vagina. Additionally, or alternatively, a surface of the fetal ECG measurement devices disclosed herein configured to contact fetal skin may include a friction-inducing surface feature (e.g., texture or compound that may make a hydrogel with adhesive properties when mixed with amniotic fluid) that, for example, assists with holding the contact surface of a fetal ECG measurement device against the fetal skin and / or prevents sliding or movement of the contact surface when positioned on the fetal skin.

[0043] In some embodiments, the fetal ECG measurement devices disclosed herein may include a wand, handle, and / or positioning device (at times, collectivelyreferred to herein as “positioning device”) configured to allow a clinician to push the fetal ECG measurement device through the vagina and cervix to contact an amniotic sac and / or fetal skin. The positioning device may be stiff enough to aid in placement of the fetal ECG measurement device but flexible enough so that it does not rupture or traumatize tissue and / or an amniotic sac during insertion and / or use. On some occasions, the wand and / or positioning device may also protect components of the fetal ECG measurement device from, for example, mechanical and / or liquid-induced damage.

[0044] The systems, devices, and methods disclosed herein overcome the safety and accuracy concerns of traditional methods of fetal ECG and heart rate monitoring especially when, for example, monitoring fetal heart rate using traditional transabdominal Doppler ultrasound is inadequate and / or use of traditional fetal scalp electrodes is contraindicated or not available due supply-chain and / or recall-induced shortages.

[0045] Turning now to the figures, FIG. 1 provides a block diagram of an exemplary system 100 for measuring and / or monitoring fetal heart rate. System 100 includes a fetal ECG measurement device 110, an optional receiver / interface 115, an optional computer and / or processor 120, and a display and / or printout device 125. At times, system 100 and / or fetal ECG measurement device 110 may also include one or more reference electrode(s) (not shown). The components of system 100 may be coupled together via wired and / or wireless communication links. In some instances, wireless communication of one or more components of system 100 may be enabled using short-range wireless communication protocols designed to communicate over relatively short distances (e.g., Bluetooth®, near field communication (NFC), radiofrequency identification (RFID), and Wi-Fi)) with, for example, a computer or personal electronic device (e.g., tablet computer or smart phone).

[0046] Fetal ECG measurement device 110 may be used to detect, monitor, and / or measure a feature of a fetus’s heart rate and / or cardiac signal via direct contact with fetal skin and / or indirect electrical coupling with the fetus via insertion into an endocervical canal of a pregnant mammal until it is in contact with fetal skin and / or is proximate enough to fetal skin to be electrically coupled thereto via, for example, a conducting fluid like amniotic fluid (e.g., inside and / or outside the amniotic sac). Once in position, the fetal ECG measurement devices 110 disclosed herein may detect electrical signals from the fetus using one or more ECG leads and, on some occasions,a reference electrode that may be in contact with maternal tissue (e.g., vaginal canal or thigh). ECG leads may be an electrode, lead, and / or sensor configured to detect an electrical signal and / or electrical potential generated by a fetus’s heart. In some embodiments, the ECG leads may be configured to provide feedback regarding whether or not fetal ECG measurement device 110 is in contact with fetal skin and / or is electrically coupled to the fetus because when it is decoupled (physically or electrically) from the fetus (e.g., an ECG lead is not in contact with fetal skin and is potentially floating in amniotic fluid surrounding the fetus in a manner that does not allow for electrical coupling of the ECG lead to the fetus), a low impedance path may exist between two ECG leads that is different from the impedance measured between these two leads when they are in contact with and / or electrically coupled to the fetus. This impedance difference can be measured using, for example, ECG lead-off detection circuitry and / or other bioimpedance measurement devices, either, or both, of which may be resident within receiver / interface 115 and / or computer and / or processor 120 and or be embodied as a separate device that may be coupled thereto In some embodiments, one or more ECG lead(s) may be positioned so that they are in physical contact with and / or electrically coupled to the fetus and additional ECG lead(s) may be positioned so that they may be in contact with, for example, maternal tissue (e.g., skin, vaginal wall, and / or uterine wall) when fetal ECG measurement device 110 is in situ within a pregnant mammal’s body / uterus.

[0047] Optional receiver / interface 115 may communicate signals received from fetal ECG measurement device 110 to computer and / or processor 120 and / or display and / or printout device 125. Additionally, or alternatively, receiver / interface 115 may be configured to perform signal conditioning (e.g., analog filtering, digital filtering, amplification, etc.) upon one or more received raw ECG signal(s). Computer and / or processor 120 may act to process the received raw ECG signal(s) and / or conditioned ECG signal(s), according to, for example, one or more of the methods disclosed herein, and facilitate provision of the results (e.g., fetal heart rate and / or trends for fetal heart rate) to display and / or printout device 125. Exemplary computers 120 include desktop and laptop computers, servers, tablet computers, personal electronic devices, mobile devices (e.g., smart phones), ECG machines, and the like.

[0048] In some embodiments, receiver / interface 115 and / or computer and / or processor 120 may be configured to amplify raw, differential, and / or conditioned ECG signal(s) via, for example a differential amplifier included therein. The differentialamplifier may be configured to convert the differential signal into a single-ended output.

[0049] In some embodiments, display and / or printout device 125 may be configured to communicate with, and / or be resident within, processor and / or computer 120 and, in these embodiments, exemplary display and / or printout devices 125 may be embodied as computer monitors, tablet computer devices, display screens, computer monitors, and the like. Additionally, or alternatively, display and / or printout device 125 may be embodied as a strip chart recorder or other printing device configured to receive a raw analog ECG signal from ECG measurement device 110 and / or receiver / interface 115 and / or a conditioned analog ECG signal from receiver / interface 115 and the analog raw and / or conditioned analog ECG signal may drive the display and / or printout device 125 (embodied as, for example, a strip chart recorder) to graph, or otherwise print out the raw and / or conditioned ECG signal and / or fetal heart rate data determined therefrom.

[0050] FIG. 2A provides a schematic diagram of a top plan view of a first exemplary system 201 that includes a first fetal ECG measurement device 110A and an optional external reference electrode 285 that may be put in contact with non-fetal tissue such as a vaginal canal or maternal leg. First fetal ECG measurement device 110A includes a positioning extension 210 that houses an optional inflation line 215, an optional marker 239, and a cord, or wire, 220 configured to, for example, provide electricity to first ECG measurement device 110A and / or enable communication of, for example, ECG signals received by an ECG lead 250 to computer and / or processor 120. First fetal ECG measurement device 110A also includes a first housing 205A sized, shaped, and configured to house ECG lead 250, and required circuitry for its operation and communication with system 100 and / or components thereof such as a communicative coupling between ECG lead 250 and wire 220. In some embodiments, positioning extension 210 may include an internal reference electrode 280 positioned and configured to contact and / or electrically couple to maternal tissue such as the uterus, cervix, and / or vagina. In some embodiments, data from first fetal ECG measurement device 110A may be used with data from internal reference electrode 280 and / or an optional external reference electrode 285 to, for example, perform one or more methods disclosed herein.

[0051] Optionally, first exemplary system 201 and / or first housing 205A may include a fetal temperature sensor 235 configured to sense a temperature of the fetusand / or uterus while first housing 205A is in situ proximate to fetal skin. Additionally, or alternatively, first fetal ECG measurement device 110A (e.g., positioning extension 210) may include a maternal temperature sensor 237 configured to sense a temperature of maternal tissue (e.g., the cervix and / or vagina) while, for example, positioning extension 210 is positioned therein and / or first housing 205A is in situ proximate to fetal skin. Additionally, or alternatively, first fetal ECG measurement device 110A and / or first housing 205A may include an optional marker 239 configured to, for example, be opaque when one or more imaging technologies are used to image the fetal and / or maternal tissue. For example, marker 239 may be echogenically and / or radio opaque so that it is easily visualized when, for example, a pregnant mammal’s abdomen and / or the fetus is imaged using, for example, ultrasound and / or other imaging technology. Thus, marker 239 may be configured to assist clinicians with visualization of a position of first housing 205A and / or first fetal ECG measurement device 110A relative to maternal and / or fetal anatomy during use.

[0052] Additionally, or alternatively, first fetal ECG measurement device 110A may include one or more optional engagement feature(s) 252 configured to increase friction and / or grippiness between first housing 205A and the fetal skin. Engagement feature(s) 252 may include, for example, a rubber or silicone feature that has an approximately uniform smooth surface, an approximately uniform rough surface, and / or a plurality of features (e.g., ridges, nubs, and / or divots) configured to removably engage with fetal skin and increase a coefficient of friction between the fetal skin and first housing 205A, thereby decreasing a likelihood that first housing 205A will slip off, or otherwise disengage from, the fetal skin. The features of engagement feature(s) 252 may be arranged in any pattern (e.g., dots, stripes, zig-zags, curved lines, etc.). Although engagement feature(s) 252 are shown to surround an exterior of first housing 205A, this need not always be the case. For example, in some embodiments, one or more engagement feature(s) 252 may be positioned on a surface of first housing 205A including ECG lead 250 and / or another (e.g., back or side) surface of first housing 205A and / or positioning extension 210.

[0053] FIG. 2B1 provides a schematic diagram of a top plan view of a second exemplary fetal ECG measurement device 110B that includes positioning extension 210, optional inflation line 215, cord 220, optional engagement feature(s) 252, and optional maternal temperature sensor 237. Second fetal ECG measurement device 110B also includes a second housing 205B sized, shaped, and configured to house afirst ECG lead 250A, a second ECG lead 250B, optional fetal temperature sensor 235, optional marker 239, and circuitry used for operation of second exemplary fetal ECG measurement device 11 OB and communication with system 100 and / or components thereof (e.g., communicative and / or electrical couplings between first and second ECG leads 250A, 250B, and optional temperature sensor and cord 220).

[0054] Second housing 205B also includes a first optional non-conductive, electrically-isolating element 240A (also referred to herein as “first electrically-isolating element 240A”) sized, configured, and positioned to surround first ECG lead 250A and electrically isolate it from second ECG lead 250B and a second optional non- conductive, electrically-isolating, element 240B (also referred to herein as “second electrically-isolating element 240B”) sized, configured, and positioned to surround second ECG lead 250B and electrically isolate it from first ECG lead 250A. First and / or second optional electrically-isolating element(s) 240A and / or 240B may be embodied as a raised projection that extends above (e.g., 0.1-5mm) a surface of first and / or second ECG lead(s) 250A and / or 250B that acts to contain any fluid (e.g., amniotic fluid) surrounding their respective ECG leads so that the first and second ECG leads 250A and 250B and fluid proximate thereto are electrically isolated from one another, thereby preventing electrical communication between first and second ECG leads 250A and 250B via, for example, amniotic fluid. In some embodiments, second fetal ECG measurement device 110B may include only first or second electrically-isolating element 240A or 240B. For example, first electrically-isolating element 240A may electrically insulate ECG lead 250A from ECG lead 250B without second electrically- isolating element 240B.

[0055] FIG. 2B2 provides a schematic diagram of a cross section (taken along line 2B2-2B2 of FIG. 2B1 ) of second exemplary fetal ECG measurement device 110B when positioned in utero proximate to fetal skin. As may be seen in FIG. 2B2, when second exemplary fetal ECG measurement device 110B is positioned proximate to fetal skin 292 in utero, first electrically-isolating element 240A may contact fetal skin 292 and electrically isolate a volume of amniotic fluid 294 from a surrounding, ambient, volume of amniotic fluid 292 that may, or may not, be in electrical contact with second ECG lead 250B. Optional second electrically-isolating element 240B may be configured to operate in a manner similar to that of first electrically-isolating element 240A shown in, for example, FIG. 2B2.

[0056] FIG. 2C provides a schematic diagram of a top plan view of a third exemplary fetal ECG measurement device 110C that includes all the components of second fetal ECG measurement device 110B as well as a third ECG lead 250C and a third optional electrically-isolating element 240C sized, configured, and positioned to surround third ECG lead 250C and electrically isolate it from first and second ECG leads 250A and 250B. Second and / or optional third electrically-isolating element(s) 240B and / or 240C may be configured to operate in a manner similar to that of first electrically-isolating element 240A shown in, for example, FIG. 2B2.

[0057] FIG. 2D1 provides a schematic diagram of a top plan view of a fourth exemplary fetal ECG measurement device 110D that includes a fourth housing 205D and positioning extension 210, which includes cord 220, optional inflation line 215, optional internal reference electrode 280, and optional maternal temperature sensor 237. Fourth housing 205D houses first ECG lead 250A, second ECG lead 250B, third ECG lead 250C, optional fetal temperature sensor 235, optional marker 239, optional engagement feature(s) 252, and a first exemplary mechanical barrier 260 comprising a vertical component 260A positioned between second and third ECG leads 250B and 250C and a horizontal component 260B positioned between first and second ECG leads 250A and 250B. Mechanical barrier 260, vertical component 260A and / or horizontal component 260B may be embodied as a projection that extends (e.g., 0.1- 5mm) above fourth housing 205D and / or a contact surface of first, second, and third ECG leads 250A, 250B, and 250C as shown. First mechanical barrier 260 may be, for example, “T-shaped and / or have any other shape (e.g., a “Y”-shape) that allows it to be positioned between first, second, and third ECG leads 250A, 250B, and 250C. First mechanical barrier 260 may be configured to, for example, standardize and / or control a magnitude of impedance induced by amniotic fluid across first, second, and / or third ECG leads 250A, 250B, and 250C by, for example, creating a standard thickness of the fluid layer positioned between first, second, and / or third ECG lead(s) 250A, 250B, and / or 250C and fetal skin that may be less sensitive to scenarios when first, second, and third ECG lead(s) 250A, 250B, and / or 250C is / are separated and / or partially lifted away from fetal skin.

[0058] FIG. 2D2 provides a schematic diagram of a vertical cross section of fourth housing 205D taken along cross section line 2D2-2D2 and shows how vertical component 260A extends proud from a surface of fourth housing 205D to isolate first and second ECG leads 250A and 250B from third ECG lead 250C (not shown). FIG.2D2 also shows how horizontal component 260B extends proud from the surface of fourth housing 205D to isolate first ECG lead 250A from second ECG lead 250B.

[0059] FIG. 2D3 provides a schematic diagram of a horizontal cross section (taken along line 2D3-2D3 of FIG. 2D1 ) of fourth exemplary fetal ECG measurement device 110D when positioned in utero proximate to fetal skin 290. As may be seen in FIG. 2D3, when fourth housing 205D is positioned proximate to fetal skin 292 in utero, horizontal component 260B may contact fetal skin 292 and electrically isolate a first volume of amniotic fluid 296 proximate to and / or in electrical contact with second ECG lead 250B from a second volume of amniotic fluid 297 that may be proximate to and / or in electrical contact with third ECG lead 250C.

[0060] FIG. 2E1 provides a schematic diagram of a top plan view of a fifth exemplary fetal ECG measurement device 110E that includes positioning extension 210, which includes cord 220, optional inflation line 215, optional internal reference electrode 280, optional engagement feature(s) 252, optional maternal temperature sensor 237, and a fifth housing 205E that houses the first ECG lead 250A, second ECG lead 250B (which may be optional), third ECG lead 250C (which may be optional), optional fetal temperature sensor 235, optional marker 239, and an exemplary second mechanical barrier embodied as a trough that is depressed (e.g., 0.1-5mm) into a surface of fifth housing 205E proximate to a contact surface of first, second, and third ECG leads 250A, 250B, and 250C as shown. Second mechanical barrier 265 may be configured to, for example, standardize and / or control a magnitude of impedance induced by amniotic fluid across first, second, and third ECG leads 250A, 250B, and 250C by, for example, creating a standard thickness of the fluid layer positioned between first, second, and / or third ECG lead(s) 250A, 250B, and / or 250C and fetal skin that may be less sensitive to scenarios when first, second, and third ECG leads 250A, 250B, and / or 250C is separated and / or partially lifted away from fetal skin.

[0061] In some embodiments, second mechanical barrier 265 may be configured to drain amniotic fluid away from fetal skin by, for example, directing the amniotic fluid away from the fetal skin and / or containing the amniotic fluid, thereby leaving an air gap between second and third ECG leads 250B and 250C so that second and third ECG leads 250B and 250C touch and / or are in contact with the fetal skin without any intervening amniotic fluid. Optionally barriers 266 may be positioned at an edge of and / or surrounding first, second, and / or third ECG leads 250A, 250B,and / or 250C may create an air gap 298 as, for example shown in FIG. 2E3. In some embodiments, optional barrier 266 may comprise and / or be coated with a hydrophilic material and first, second, and / or third ECG leads 250A, 250B, and / or 250C and / or areas proximate to first, second, and / or third ECG leads 250A, 250B, and / or 250C may comprise and / or be coated with hydrophobic materials to assist with wicking the amniotic fluid away from first, second, and / or third ECG leads 250A, 250B, and / or 250C.

[0062] FIG. 2E2 provides a schematic diagram of a cross section view of fifth housing 205E taken along section line 2E2-2E2 when positioned in utero proximate to fetal skin 290. As may be seen in FIG. 2E2, second and third ECG leads 250B and 250C may be positioned proximate to fetal skin 290and a portion of ambient amniotic fluid 299 may be positioned within trough 265, which may act to standardize and / or control a magnitude of impedance induced by amniotic fluid across second and third ECG leads 250B and 250C.

[0063] First, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E may be physically coupled (e.g., bonded, affixed, and / or joined) to positioning extension 210. In some cases, a joint between first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E and positioning extension 210 may be configured to articulate to, for example, enable insertion and / or proper positioning of housing 205A, 205B, 205C, 205D, and / or 205E on fetal skin and / or within the uterus so that it may be electrically coupled to the fetus via contact with fetal skin and / or conductive (e.g., amniotic) fluid.

[0064] In some embodiments, positioning extension 210 may also include optional inflation line 215 with a lumen therein configured to provide inflating fluid (e.g., saline, air, water, etc.) to an optional inflatable stabilization device 225 (see e.g., FIG. 2F). Optional inflatable stabilization device 225 may be configured to be positioned between an active surface of first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E (e.g., a surface that holds first, second, and / or third ECG lead 250A, 250B, and / or 250C) and an internal uterine wall. Optional inflatable stabilization device 225 may be inflated and / or adjusted to occupy space between fetal skin and a uterine wall so that it presses the active surface of first, second, third, fourth and / or fifth fetal ECG measurement device 110A, 110B, 110C, 110D and / or 110E, first, second, and / or third ECG leads 250A, 250B, and / or 250C, and / or first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E against the fetalskin and / or assists with maintaining contact between the fetal skin and an ECG lead 250 (e.g., first, second, and / or third ECG leads 250A, 250B, and / or 250C). In some embodiments, a degree to which optional inflatable stabilization device 225 is inflated / deflated may be responsive to, for example, a degree of back pressure exerted on optional inflation line 215 (as measured by, for example, an optional pressure gauge 282 (shown in FIG. 2F)), a degree of pressure required to further inflate optional inflatable stabilization device 225 (as, for example, measured by optional pressure gauge 282), and / or a measurement taken from one or more components of fetal ECG measurement device 110A, 11 OB, 110C, and / or 110D (e.g., a degree of inflation may be adjusted so to establish and / or improve the readings from first, second, and / or third ECG lead(s) 250A, 250B, and / or 250C). Optional pressure gauge 282 may be, for example, an analog pressure meter, a force meter, a Bourdon pressure gauge, and / or a pressure-sensitive resistance meter.

[0065] Additionally, or alternatively, in some embodiments, a degree of inflation of optional inflatable stabilization device 225 may be responsive to a position of the fetus within the uterus and / or birth canal and may be configured to, for example, deflate as a labor and delivery process of the fetus transitions from, for example, the first to the second stage of labor. Deflation of optional inflatable stabilization device 225 in this manner may assist with reducing an overall size / profile of first, second, third, fourth, or fifth fetal ECG measurement device 110A, 11 OB, 110C, 110D, or 110E so that, for example, it does not interfere with the movement of the fetus through the birth canal during delivery.

[0066] In some embodiments, optional inflatable stabilization device 225 may be configured to expand and / or fill space until an external pressure is exerted thereon. In these embodiments, optional inflatable stabilization device 225 may comprise a material (e.g., foam) configured to expand upon contact with water or amniotic fluid and fill a space between fetal skin and an inner uterine wall so that, for example, an ECG lead 250 may contact and / or be held in place relative to fetal skin or be electrically coupled to the fetus via a conductive fluid like amniotic fluid. Additionally, or alternatively, optional inflatable stabilization device 225 may comprise a deformable material (e.g., gel and / or memory foam) configured to deform and / or mold to fill a space between fetal skin and an inner uterine wall, thereby providing a close fit between an active, ECG lead containing side of first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E and fetal skin.

[0067] In some embodiments, first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E may further include an optional ECG lead 255 configured and positioned to contact and / or be electrically coupled with a pregnant mammal’s uterine wall as shown in the side views of FIGs. 2F and 2G, wherein FIG. 2G is a side view of first, second, third, fourth or fifth fetal ECG measurement device 110A, 11 OB, 110C, 110D, or 110E that includes an exemplary extension 270 positioned on an outer surface of first, second, third, fourth, and / or fifth housings 205A, 205B, 205C, 205D, and 205E opposite the active surface thereof that includes ECG lead 250 and / or first, second, and third ECG leads 250A, 250B, and 250C as shown. ECG lead 255 may be positioned anywhere along the back side of, for example, extension 270. Extension 270 may be configured to assist with the positioning and / or maintaining a position of first, second, third, fourth, or fifth fetal ECG measurement device 110A, 110B, 110C, 110 D , or 110E against fetal skin and / or proximate enough to the fetal skin to electrically couple to the fetus within a pregnant mammal’s uterus by, for example, exerting a force on the uterine wall that acts to push first, second, third, fourth, or fifth fetal ECG measurement device 110A, 110B, 110C, 110D, or 110E in the opposite direction (i.e., toward fetal skin) and, in this way, may help with keeping first, second, third, fourth, or fifth fetal ECG measurement device 110A, 110B, 110C, 110D, or 110E correctly in contact with fetal skin and / or electrically coupled to the fetus. In some embodiments, extension 270 may be flexible and / or configured to apply a controlled range of force the uterine wall, which is translated into pressing into the fetal skin and / or fetal cheek.

[0068] FIG. 3A provides a schematic diagram of a diagram of a top view of an exemplary fetal ECG measurement device 11 OF that is configured for placement on a presenting fetal head without entering the uterus (e.g., attached via insertion through the vagina and / or cervix). Fetal ECG measurement device 110F includes a first base 305A that holds optional fetal temperature sensor 235, optional marker 239, optional ECG lead 255, and first, second, and third ECG leads 250A, 250B, and 250C. An outer perimeter of base 305 is encircled by an optional attachment feature 310 configured to assist with holding fetal ECG measurement device 11 OF in place on the fetal head via a suction fit that may be similar to the way a suction cup fits to a surface. Attachment feature 310 may be, for example, an adhesive and / or a mechanical coupling device like a flange that may expand outward when fetal ECG measurementdevice 110F is pressed into fetal skin (e.g., presenting head) in a manner similar to that of a suction cup.

[0069] FIG. 3B provides a schematic diagram of a diagram of a top view of another exemplary fetal ECG measurement device 110G that is configured for placement on a presenting fetal head without entering the uterus (e.g., attached via insertion through the vagina and / or cervix). Fetal ECG measurement device 110G includes a second base 305B, which holds a single ECG lead 250, optional marker 239, and optional attachment feature 310. In some embodiments, an ECG lead 250 may be incorporated into and / or instantized in attachment feature 310 as shown in FIG. 3C, which provides a schematic diagram of a top view of a fetal ECG measurement device 110H that is configured for placement on a presenting fetal head without entering the uterus (e.g., attached via insertion through the vagina and / or cervix). Fetal ECG measurement device 11 OH includes a single ECG lead 250, optional marker 239, and optional fetal temperature sensor 235.

[0070] When attachment feature 310 is insufficient, or not present, fetal ECG measurement device(s) 11 OF, 110G, and / or 11 OH may be attached to the skin of the fetal head via any appropriate means including, but not limited to, tape, gel, and / or an adhesive.

[0071] As may be seen in the schematic diagram of a cross-section view of FIG. 3D taken along line 3D-3D of FIGs. 3A, 3B, or 3C, fetal ECG measurement devices 110F, 110G, and 110H may also include an optional positioning device 325 configured to assist with the insertion of fetal ECG measurement device 11 OF into the vagina and / or attaching first, second, or third base 305A, 305B, or 305C to the fetal head so that one or more ECG leads 250 may be proximate to and / or in electrical contact with fetal skin and optional attachment feature 310 may be engaged to, for example, hold fetal ECG measurement devices 11 OF, 110G, or 11 OH in place during use. In some embodiments, positioning device 325 may be configured in a manner similar to positioning extension 210. Positioning device 325 may include cord 220 and optional maternal temperature sensor 237. Additionally, or alternatively, in some embodiments, positioning extension 210 may be configured to decouple from first, second, and / or third base 305A, 305B, and / or 305C via, for example, a mechanical or magnetic coupling between positioning extension 210 and first, second, and / or third base 305A, 305B, and / or 305C. Optionally, fetal ECG measurement devices 11 OF, 110G, and 11 OH may also include internal reference electrode 280 resident within and / orextending from positioning device 325. Additionally, or alternatively, fetal ECG measurement devices 110F, 110G, and 110H may be included in a system comprising fetal ECG measurement devices 110F, 110G, and 110H may also include and external reference electrode 285. Optionally, fetal ECG measurement devices 11 OF, 110G, and 110H may also include ECG lead 255 which may be configured and / or positioned to contact maternal tissue (e.g., cervix and / or vagina) and, in some instances, may provide reference electrode data.

[0072] FIG. 4 provides a flowchart illustrating a process 400 for generating an electrocardiogram (ECG) for a fetus and / or determining a fetal heart rate using, for example, one or more of the systems, devices, and / or system components disclosed herein.

[0073] Initially, in step 405, data are received from one or more ECG leads in electrical contact with fetal skin while the fetus is still in utero or has entered the birth canal. At times, the ECG data received in step 405 may be raw ECG data received from, for example, first, second, and / or third ECG lead(s) 250A, 250B, and / or 250C. In some embodiments, the one or more ECG leads may be positioned on an outside surface of a pregnant mammal’s amniotic sac and electrical communication with the fetal skin may be facilitated by amniotic fluid present within the amniotic sac. Additionally, or alternatively, the one or more ECG leads may be positioned inside of a pregnant mammal’s amniotic sac and / or uterus before the fetal head enters the pregnant mammal’s cervix and / or vagina. In some embodiments, temperature data from, for example, fetal temperature sensor 235 and / or maternal temperature sensor 237 may be received in step 405.

[0074] Optionally, in step 410, it may determined whether there is an indication of an error condition present in the data received in step 405 as may occur when one or more of the ECG leads is not in contact with the fetal skin (e.g., floating in amniotic fluid or air) and, if so, providing an indication of the error to a display device (e.g., display and / or printout device 125) in communication with a processor (e.g., computer and / or processor 120) performing process 400 (step 415). In some embodiments, execution of step 410 may include determining a level of impedance indicated by the received data and providing an error indication to the display device responsively to an indication that the level of impedance is outside (e.g., above or below) a range of values (e.g., 1 ,900-16,000 ohms, 1 ,000-20,000 ohms or 800-25,000 ohms). Additionally, or alternatively, execution of step 410 may include determining a level ofelectrical shunting indicated by the received data and providing an error indication to the display device responsively to an indication that the level of electrical shunting is above a threshold. Execution of step 415 may include illuminating an error light (e.g., a yellow or blue LED or series of LEDs) or displaying a message such as the phrase(s) “lead off’ and / or “insufficient contact” on a display device like display and / or printout device 125. Additionally, or alternatively, the error indication may be an instruction and / or recommendation that may reduce an effect of the error. For example, when the one or more ECG leads are positioned within first, second, third, fourth, and / or fifth housing 205A, 205B, 205C, 205D, or 205E, the error indication may include an instruction or recommendation to adjust an orientation and / or position of positioning extension 210, adjust an orientation and / or position of first, second, third, fourth, or fifth housing 205A, 205B, 205C, 205D, or 205E, and / or adjust a level of inflation of optional inflatable stabilization device 225.

[0075] Optionally, in step 420, the ECG data (e.g., raw ECG data) may be conditioned (e.g., using analog filtering, digital filtering, amplification, etc.) or otherwise processed to, for example, calculate the voltage difference between the ECG electrode and selected reference electrode, remove noise, and / or improve signal quality. At times, receiver / interface 115 may perform step 420.

[0076] Optionally, in step 425, fetal heart rate data (e.g., beats per minute, trends over time, etc.) may be prepared using, for example, the ECG data of step 405 and / or the conditioned ECG data of step 420 may be determined or otherwise prepared. The fetal heart rate may be determined via any acceptable method including, but not limited to, performing R-wave detection and calculating a R-wave interval measurement, determining a number of R waves / minute, determining a number of QRS complexes / minute, using a mean or average time between consecutive QRS complexes, determining a change in fetal heart rate over time, using frequency analysis (e.g., fast Fourier transforms) to determine fetal heart rate, and / or determining a time-weighted average of fetal heart rate.

[0077] In step 430, the fetal ECG data of step 405, the conditioned fetal ECG data of step 420, the fetal heart rate of step 425, and / or temperature data may then be provided to a display device, such as display and / or printout device 125. When temperature data is provided, it may be used by a clinician to, for example, diagnose infection.

[0078] In some embodiments, process 400 may be executed using analog equipment and / or signals. In these embodiments, the ECG data of step 405 and / or the conditioned ECG data of step 420 may be directly received by a printout device like display and / or printout device 125 when display and / or printout device 125 is embodied as, for example, a strip chart recorder. The received ECG data may drive the printout device to generate a physical printout of the ECG data. In these embodiments, process 400 may only include steps 405, 420, and 430; with execution of step 420 being optional.

[0079] For embodiments disclosed herein that include a plurality of ECG leads configured and / or positioned to be in contact with fetal skin, execution of process 400 may include selecting ECG data (including the reference signal) from one or more of the plurality of ECG leads based upon, for example, signal strength (e.g., amplitude and / or power), impedance, and / or clarity (e.g., high signal-to-noise ratio) for further analysis (e.g., execution of step(s) 425 and / or 430). This may be effective when, for example, one (or more) ECG lead(s) lifts off the fetal skin with another ECG lead remains in contact.

Claims

CLAIMS\Ne claim:1 . A fetal electrocardiogram (ECG) measurement device comprising: an ECG lead configured to be in electrical communication with skin of a fetus in utero, communicatively coupled to at least one of a processor and a receiver, and provide ECG measurements to the at least one processor and receiver; and a positioning extension configured to enable positioning the ECG lead onto the skin of the fetus while the fetus is in utero.

2. The fetal ECG measurement device of claim 1 , wherein the ECG lead is a first ECG lead, the device further comprising: a second ECG lead configured to be in electrical communication with the skin of the fetus, communicatively coupled to the at least one processor and receiver, and provide ECG measurements to the at least one processor and receiver.

3. The fetal ECG measurement device of claim 2, further comprising: a mechanical barrier sized, configured, and positioned to electrically insulate the first ECG lead from the second ECG lead.

4. The fetal ECG measurement device of claim 3, wherein the mechanical barrier is configured as an extension that extends from a surface of the device proximate to at least one of the first ECG lead and the second ECG lead.

5. The fetal ECG measurement device of claim 3, wherein the mechanical barrier is trough that extends into a surface of the device between the first ECG lead and the second ECG lead.

6. The fetal ECG measurement device of claim 5, wherein the mechanical barrier is configured to control a magnitude of impedance induced by amniotic fluid across the first and second ECG leads.

7. The fetal ECG measurement device of claim 2, further comprising:an electrically-isolating element sized, configured, and positioned to electrically insulate the first ECG lead from the second ECG lead.

8. The fetal ECG measurement device of claim 7, wherein the electrically-isolating element is configured as an extension that extends from a surface of the device and surrounds the first ECG lead so that a volume of amniotic fluid may be contained within the electrically-isolating element, wherein the volume of amniotic fluid contained within the electrically-isolating element is electrically isolated from the second ECG lead.

9. The fetal ECG measurement device of claim 2, further comprising: a first electrically-isolating element sized, configured, and positioned to electrically insulate first ECG lead from second ECG lead; and a second electrically-isolating element sized, configured, and positioned to electrically insulate second ECG lead from first ECG lead.

10. The fetal ECG measurement device of any of the above claims, wherein the positioning extension includes a reference electrode positioned and configured to contact and / or electrically couple to maternal tissue.11 .The fetal ECG measurement device of any of the above claims, wherein the positioning extension includes a cord configured to electrically and / or communicatively couple to the ECG lead and the at least one processor and receiver.

12. The fetal ECG measurement device of any of the above claims, further comprising: a housing comprising a first side in which the ECG lead is positioned; and a stabilization device positioned on a second of the housing, the second side of the housing opposing the first side of the housing.

13. The fetal ECG measurement device of claim 12, wherein the stabilization device is configured to face an internal uterine wall when in situ.

14. The fetal ECG measurement device of claim 12 or 13, wherein a size and / or volume of the stabilization device is adjustable.

15. The fetal ECG measurement device of claim 14, wherein the stabilization device is inflatable, the fetal ECG measurement device further comprising: an inflation line resident in the positioning extension, the inflation line being in communication with the stabilization device and configured to communicate fluid to and / or from the stabilization device, thereby adjusting a size and / or volume of the stabilization device.

16. The fetal ECG measurement device of claim 15, wherein a degree of inflation of the stabilization device is responsive to back pressure exerted on the inflation line.

17. The fetal ECG measurement device of claim 15, wherein a degree of inflation of the stabilization device is responsive to ECG data.

18. The fetal ECG measurement device of any of claims 12-17, wherein the stabilization device comprises a material that expands when exposed to amniotic fluid.

19. The fetal ECG measurement device of any of claims 12-18, wherein the stabilization device comprises a material that expands into space between the fetus and internal uterine wall.

20. The fetal ECG measurement device of any of claims 12-19, wherein the stabilization device is configured to occupy space between the fetus and internal uterine wall and assist with maintaining contact between the fetal skin and the ECG lead.21 .The fetal ECG measurement device of any of the above claims, further comprising: a housing comprising an active side in which the ECG lead is positioned; and an extension positioned on a surface of the housing opposing the active side of the housing, the extension being configured to assist with positioning and / or maintaining a position the ECG measurement device proximate to the fetal skin.

22. The fetal ECG measurement device of any of the above claims, further comprising: a housing comprising a first side in which the ECG lead is positioned; and a reference electrode positioned on a second side of the housing, the reference electrode being positioned and configured to contact and / or be electrically coupled with a uterine wall of a mammal who is pregnant with the fetus.

23. The fetal ECG measurement device of any of the above claims, wherein the skin is at least one of a cheek, a back, a head, an arm, and a chest of the fetus.

24. The fetal ECG measurement device of any of the above claims, further comprising: a temperature sensor configured to measure a temperature of the fetus and / or a mammal who is pregnant with the fetus.

25. The fetal ECG measurement device of any of the above claims, further comprising: a marker configured to be opaque to an imaging technology.

26. The fetal ECG measurement device of any of the above claims, further comprising: an engagement mechanism configured to hold the fetal ECG measurement device against the fetal skin during use.

27. A method of using the fetal ECG measurement device of any of the above claims to obtain fetal ECG measurement data.

28. A method of using the fetal ECG measurement device of any of claims 1-26 to generate a fetal ECG.

29. A method of using the fetal ECG measurement device of any of claims 1-26 to determine fetal heart rate data.

30. A method for generating an electrocardiogram (ECG) for a fetus: receiving, by a processor, data from an ECG lead in electrical communication with fetal skin positioned within a pregnant mammal’s uterus; generating, by the processor, the ECG for the fetus using the received data; and providing, by the processor, the ECG for the fetus to a display device.31 .The method of claim 30, further comprising: receiving, by the processor, data from a reference electrode, wherein generating the ECG for the fetus further uses the data from the reference electrode.

32. The method of claim 30 or 31 , further comprising: determining, by the processor, a level of impedance indicated by the received data; and providing, by the processor, an error indication to a display device responsively to an indication that the level of impedance is above a threshold.

33. The method of any of claims 30-32, further comprising: determining, by the processor, a level of shunt indicated by the received data; and providing, by the processor, an error indication to a display device responsively to an indication that the level of shunt is outside a range of values.

34. The method of any of claims 30-33, further comprising: determining, by the processor, whether there is an error condition present within the received data and, if so, providing an error message to the display device.

35. The method of any of claims 30-34, further comprising: determining, by the processor, fetal heart rate data using the ECG for the fetus; and providing, by the processor, the fetal heart rate data to the display device.

36. The method of any of claims 30-35, wherein the fetal skin is at least one of a cheek, a back, a head, an arm, and a chestof the fetus.

37. The method of any of claims 30-36, further comprising: receiving, by the processor, temperature data from a temperature sensor positioned in a uterus of a mammal who is pregnant with the fetus; and providing, by the processor, the temperature data to the display device.

38. A method for generating an electrocardiogram (ECG) for a fetus: receiving, by a printout device, ECG data from an ECG lead in electrical communication with fetal skin within a uterus; and generating, by the printout device, a printout of the ECG data.

39. The method of claim 38, wherein the ECG data is received by a receiver prior to the ECG data being received by the printout device, the receiver being in communication with the printout device, the method further comprising: conditioning, by the receiver, the ECG data prior to communication to the printout device; and communicating, by the receiver conditioned ECG data to the printout device, wherein the printout device generates a printout of a result of the conditioned ECG data.

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