Apparatus for monitoring pregnancy or labor
Patent Information
- Application Number
- JP2024203712
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2016-12-07
- Filing Date
- 2024-11-22
- Publication Date
- 2025-05-26
- Estimated Expiration
- Not applicable · inactive patent
Smart Images
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Abstract
Description
[Technical field]
[0001] Related Applications This application claims priority from Australian provisional patent application 2016905046, filed December 7, 2016, the contents of which are incorporated herein by reference.
[0002] Technical Field The present invention relates to a pregnancy or childbirth monitoring device. [Background technology]
[0003] Pregnancy and childbirth involve complex biological processes that to date remain poorly understood, and the majority of women who undergo labour or who give birth at a later date do not require major medical interventions. However, there is a significant population of women for whom natural childbirth is not possible or who choose not to give birth naturally. This requires interventions such as Caesarean section or operative vaginal delivery. While medical interventions have improved both maternal and fetal outcomes over the past decades and prevented death and trauma, they are still associated with significant risks and complications.
[0004] Technological advances offer the possibility of using less invasive, low-cost techniques to monitor the mechanics of labour. A better understanding of the mechanics of labour can assist clinicians in earlier identification and assessment of risk for poor pregnancy and labour progress.
[0005] The majority of current labor monitoring systems use electrocardiography (CTG), more widely known as electronic fetal monitoring (EFM). These monitoring systems use fetal heart rate and contraction frequency to predict whether birth is imminent, as well as to detect abnormalities or complications during pregnancy and labor. These systems tend to monitor fetal heart rate using a Doppler ultrasound transducer or fetal electrocardiogram (fECG). They also monitor uterine contractions using another device known as a tocodenanometer (TOCO), which is actually a strain gauge that measures the increased abdominal tension associated with contractions, or electromyography (EMG) to determine the presence of contractions. However, such systems are relatively cumbersome or uncomfortable, and difficult to record during movement or water immersion (shower, bath, or similar). Furthermore, the data provided by such devices, i.e. fetal heart rate and contraction frequency, require subjective interpretation which increases the degree of interference. These factors often limit patients to hospital environments where such systems must be available and where trained clinicians must be present to operate and interpret the systems. Furthermore, these systems only allow for limited assessment of activity during pregnancy and labor. Summary of the Invention [Means for solving the problem]
[0006] Any discussion of documents, acts, materials, devices, articles or the like contained in this specification in the field relevant to this disclosure that existed prior to the priority date of each claim of this application is not to be regarded as forming part of the prior art or as being common general knowledge in any or all of that matter.
[0007] overview According to one aspect of the present disclosure, there is provided a pregnancy or childbirth monitoring apparatus including a plurality of sensors disposed on the body and integrated into the monitoring device, the plurality of sensors including at least a first sensor configured to detect a first type of signal from the body indicative of fetal or maternal activity during pregnancy or childbirth, and a second sensor configured to detect a second type of signal from the body indicative of fetal or maternal activity during pregnancy or childbirth different from the first type of signal.
[0008] In some embodiments, both the first and second types of signals are indicative of bodily movement during pregnancy or labour, the bodily movement being fetal movement and / or maternal movement.
[0009] The first sensor may be an electromyogram sensor (EMG sensor) and the second sensor may be a temperature sensor. Alternatively, the first sensor may be an electromyogram sensor and the second sensor may be an accelerometer. Also, the first sensor may be a temperature sensor and the second sensor may be an accelerometer.
[0010] In some embodiments, fetal activity may include one or more of fetal position, fetal movement, and fetal heart rate. In some embodiments, maternal activity may include one or more of muscle and uterine contractions, maternal position, maternal movement, maternal heart rate, and maternal temperature.
[0011] In some embodiments, the types of fetal or maternal activity monitored by the different sensors may be the same.
[0012] According to one aspect of the present disclosure, a pregnancy or labor monitoring apparatus is provided, the apparatus comprising a monitoring device for placement on the body and including integrated therewith a plurality of sensors, the plurality of sensors including at least a first sensor for detecting a first type of signal from the body to provide an indication of a type of fetal or maternal activity during pregnancy or labor, and a second sensor for detecting a second type of signal, different from the first type of signal, from the body to provide an indication of the same type of fetal or maternal activity as the first sensor.
[0013] In the aforementioned embodiment, the first sensor may be an electromyogram sensor. The second sensor may be a temperature sensor. Alternatively, the first sensor may be an electromyogram sensor and the second sensor may be an accelerometer. Alternatively, the first sensor may be a temperature sensor and the second sensor may be an accelerometer.
[0014] By detecting different signals from the body with different types of sensors, each configured to provide an indication of the same type of fetal or maternal activity, collection of data regarding pregnancy and / or delivery may be more accurate and / or reliable. This may be particularly advantageous in circumstances where fetal and / or maternal movement, interventions, and the pregnancy or delivery process itself, or other circumstances may result in missed or lost data. For example, even if one sensor is interrupted by non-contact, poor contact, or other external influence, the provision of other sensors allows monitoring of at least one type of signal to continue continuously and uninterrupted. In some cases, the monitoring device may be exposed to different conditions during monitoring, such as patient movement or exposure to water, which may result in one sensor being inappropriate for monitoring in a particular situation. By detecting at least two different types of signals, each providing an indication of the same type of fetal or maternal activity, the loss or interruption of one sensor does not prevent continued monitoring of that fetal or maternal activity, since useful signals from the other sensors may remain.
[0015] In some embodiments of the device disclosed herein, the plurality of sensors may include a third sensor for detecting a third type of signal from the body indicative of fetal or maternal activity during pregnancy or labor. The third sensor may be selected from the group including an accelerometer, a temperature sensor, an electromyogram sensor, and an ultrasound sensor.
[0016] In some embodiments, the plurality of sensors may include a fourth or further sensor selected from the group including an electromyographic sensor and an ultrasonic sensor.
[0017] In some embodiments, the electromyography sensor may include, for example, an electromyography sensor, i.e., an electromyography sensor configured to monitor the uterus.
[0018] In one embodiment, the first sensor is an electromyogram sensor or an accelerometer, the second sensor is a temperature sensor, and both the first and second sensors are configured to provide an indication of muscle or uterine contractions. In one embodiment, the first sensor is an electromyogram sensor, the second sensor is a temperature sensor, and the third sensor is an accelerometer, and the first, second and third sensors are each configured to provide an indication of muscle or uterine contractions.
[0019] The monitoring device may include a housing for housing the electronic components therein. The housing may be a hermetic housing to prevent ingress of fluids.
[0020] In some embodiments, the housing may include a top surface and a bottom surface contoured for placement on the body. In one embodiment, the first sensor is an electromyogram sensor, the second sensor is a temperature sensor, and the plurality of sensors may further include an accelerometer. The electromyogram sensor may include at least one electrical contact disposed on the bottom surface of the housing. The contacts may be considered to at least partially provide an EMG electrode. The at least one electrical contact may be configured to receive and electrically couple to the EMG surface electrode and may be configured to protrude from the bottom surface such that the bottom surface is away from the body when the monitoring device is placed on the body. The temperature sensor may be disposed on the bottom surface of the housing, and the accelerometer may be disposed within the housing.
[0021] In some embodiments, the monitoring device may include a central portion and one or more flexible arms extending from the central portion. Each of the one or more flexible arms may be configured to be maneuverable relative to the central portion to facilitate placement of the monitoring device on the body. In some embodiments, the monitoring device may include four flexible arms arranged in a cross shape. Each of the flexible arms may have an end with an opening and an adhesive seal disposed around the opening. The adhesive seal may be configured to adhere to the body to secure the monitoring device to the body and form a water-resistant barrier around the opening. In one embodiment, the first sensor is an electromyogram sensor, the second sensor is a temperature sensor, and the plurality of sensors may further include an accelerometer. The electromyogram sensor may include a plurality of EMG electrodes. Both the adhesive seal and the electrodes may be at least partially removable from the device to allow replacement or cleaning as required by the method of use.
[0022] In aspects and embodiments disclosed herein, the electromyographic sensor may include at least one EMG electrode disposed at each end. For example, at least one electrical contact may be disposed at each end, and the at least one electrical contact may be configured to receive and electrically couple to the EMG surface electrode. A temperature sensor and an accelerometer may be disposed within the central portion. At least one of the arm portions may include a flex sensor.
[0023] The flex sensor allows detection of bending, flexion, extension, contraction, deformation, and / or other types of movement (e.g., changes in shape and / or dimensions) of the arm. This movement may be caused by body movement, such as abdominal movement caused by contraction and / or fetal movement. Body movement may result in relative movement of the EMG electrodes of the electromyography sensor. Thus, the one or more flex sensors allow monitoring of the relative position of two or more EMG electrodes. In addition to or instead of the flex sensor, one or more other types of sensors may be used, such as stretch sensors, for example for the purpose of monitoring the relative position of two or more EMG electrodes, which other sensors may also allow detection of changes in shape and / or dimensions of parts of the device structure.
[0024] According to one aspect of the present disclosure, there is provided a pregnancy or labor monitoring apparatus comprising an on-body monitoring device, the apparatus comprising an electromyogram sensor including two or more EMG electrodes for monitoring fetal or maternal activity during pregnancy or labor, and one or more position sensors for monitoring the relative position of the two or more EMG electrodes during fetal or maternal activity.
[0025] The one or more position sensors may be other types of sensors, such as flex sensors or stretch sensors, that can monitor bending, flexion, extension, contraction, deformation, and / or other types of changes in the structure of the monitoring device. For example, when a flex sensor or stretch sensor is used, the changes can be monitored based on, for example, changes in resistance or capacitance of components included in the sensor. Two or more EMG electrodes may be disposed on each arm, and the position sensor may monitor, for example, bending or flexing movements of the arm. The position sensor may monitor changes in the relative position of the two or more EMG electrodes during fetal or maternal activity. For example, when the EMG electrodes are fixed to the abdomen, changes in the relative position of the two or more EMG electrodes indicate deformation of the body, for example, the abdomen, during fetal or maternal activity. Monitoring the relative position of the two or more EMG electrodes during fetal or maternal activity may be determined by the distance or change in distance between the two or more EMG electrodes.
[0026] By monitoring the location of two or more EMG electrodes during fetal or maternal activity, the EMG signals obtained from those electrodes can be interpreted taking into account their relative locations, allowing for a more comprehensive analysis of the generated data, for example, it may be possible to correlate changes in the EMG signal with strains of the body adjacent to the monitoring device, strains resulting from contractions or otherwise.
[0027] The monitoring of the movement may be performed with reference to a reference position of the monitoring device. The reference position may be a central position of the monitoring device. The reference position may be, for example, a central portion of the monitoring device from which the arm extends.
[0028] The EMG electrodes may be fixed to the body, for example, by being glued to the body as in the techniques described above. The central portion may also be fixed to the body, for example, glued to the body. Thus, the electrodes and the reference position may hold their respective positions relative to the body. The portion of the monitoring device between the reference position and the electrodes may be away from the body. For example, the arms may bridge the space between the central portion and the electrode contact position with little or no contact with the body, thereby preventing the monitoring device from significantly interfering with natural movements, for example body deformations. The arms may be arched or otherwise raised on the body, as described above, or may be flexible.
[0029] The relative positions of two or more EMG electrodes may be determined based on trigonometric calculations. The length between a first EMG electrode and the reference position may be taken as the first side of a conceptual triangle, the length between a second EMG electrode and the reference position may be taken as the second side of the conceptual triangle, and the length between the two electrodes may be taken as the third side of the conceptual triangle. The angle between the first side and the second side may be a substantially constant angle, for example if the flexible arm is only flexible in the length direction, and / or may be determined based on monitoring the deflection of the arm, for example by a flex or stretch sensor in two or more dimensions. The third side of the conceptual triangle, and thus the distance between the two electrodes, may be calculated from knowledge of the lengths of the first and second sides and their relative angles. However, other types of calculations may be performed based on data from position sensors to monitor the position of the electrodes.
[0030] In any of the above aspects and embodiments, the monitoring device may be adapted to be placed on the abdomen. The monitoring device may be placed, for example, on the fundus. For example, it has been found that the location of the monitoring device, i.e., multiple sensors, on the fundus allows the monitoring device to monitor the same type of fetal or maternal activity using different types of sensors. For example, in addition to placing an electromyogram sensor or an accelerometer (e.g., as a first sensor) on the fundus to monitor an activity such as muscle contractions or uterine contractions, it has been found that, for example, a temperature sensor on the fundus can be used as a second sensor to reliably monitor the same activity such as the same muscle contractions or uterine contractions.
[0031] The apparatus may further include a user interface connected to the monitoring device, the user interface comprising a display for displaying information derived from signals detected by the plurality of sensors. The user interface may comprise one or more of a desktop computer, a laptop computer, a smartphone, a personal digital assistant, a watch, a data collection band, and other similar devices configured to display information. Additionally or alternatively, the apparatus may include a user interface integrated into the monitoring device. For example, the user interface may be an on-board indicator. The user interface may provide an indication of the type of data being collected by the monitoring device and / or an indication of the attachment of the device to the body, power levels, etc.
[0032] The device may be configured to process signals received from each of a plurality of sensors to display them on the user interface with similar indications for the same type of fetal or maternal activity, respectively. The signals may be displayed on the display as time-correlated plots, and the amplitudes of the plots may be displayed in a similar manner for corresponding types of fetal or maternal activity. For example, the signals may be processed such that the resulting change in amplitude of the plot for a first signal when a uterine contraction occurs is the same or similar to the change in amplitude of the plot for a second or further signal. The changes in amplitude of the plots may be in the same direction. The changes in amplitude of the plots may be configured to be within a factor of, for example, 4, 3, 2, or 1.5. The scale of the plots displayed by the user interface may be selected or programmed to achieve this effect.
[0033] The monitoring device may further comprise at least one reference sensor adapted to be placed on the body at a location away from the monitoring device where there is no fetal or maternal activity to provide a reference to the multiple sensors. In some embodiments, the at least one reference sensor may be adapted to be placed on the ribs. In other embodiments, the at least one reference sensor may be adapted to be placed on the hip or sternum. The at least one reference sensor may include, for example, one or more of an electromyogram sensor, a temperature sensor, an accelerometer, and an ultrasound sensor. The at least one reference sensor may be located outside the housing and may be movable relative to the housing. The at least one reference sensor may be connected to the housing via a wire that maintains a physical and / or electrical connection between the reference sensor and other components of the monitoring device, or may be connected wirelessly.
[0034] The apparatus may further include one or more roving sensors independent of the monitoring device. The one or more roving sensors may include, for example, a fetal heart rate monitor and / or a maternal heart rate monitor. Additionally or alternatively, the one or more roving sensors may include an electromyogram sensor.
[0035] In any of the aspects described herein, the device may be adapted for use in a clinical setting, such as a hospital, birthing center, or physician's surgery. Additionally or alternatively, the device may be adapted for use in a non-clinical environment, such as the home. The device may be designed as a "point-of-care" device, whether for home use or not. The device may provide a means for remotely monitoring the patient. In this regard, signals and / or other data received by the device may be transmitted, for example, by the monitoring device to a remotely located user interface for viewing or analysis by a third party. The device may provide a means for monitoring the patient during pregnancy and / or labor.
[0036] According to another aspect of the present disclosure, there is provided a method for placing a monitoring device incorporating a plurality of sensors on a body, detecting a first type of signal from the body via a first sensor of the plurality of sensors, and detecting a second type of signal different from the first type of signal via a second sensor of the plurality of sensors, the first and second types of signals being indicative of fetal or maternal activity during pregnancy or labor.
[0037] According to another aspect of the present disclosure, there is provided a method of placing a monitoring device incorporating a plurality of sensors on a body, detecting a first type of signal from the body via a first sensor of the plurality of sensors, detecting a second type of signal different from the first type of signal via a second sensor of the plurality of sensors, using the detected signal from the first sensor to monitor a type of fetal or maternal activity, and using the detected signal from the second sensor to monitor the same type of fetal or maternal activity as monitored using the first sensor.
[0038] The method may include detecting a third type of signal from the body via a third sensor of the plurality of sensors, the third type of signal may be indicative of fetal or maternal activity during pregnancy or labor.
[0039] The method may further comprise detecting a signal from a fourth or further sensor, for example selected from the group including an electromyographic sensor and an ultrasonic sensor.
[0040] The first sensor may be an electromyogram sensor and the second sensor may be a temperature sensor. Alternatively, the first sensor may be an electromyogram sensor and the second sensor may be an accelerometer. Alternatively, the first sensor may be a temperature sensor and the second sensor may be an accelerometer.
[0041] In one embodiment, the first sensor is an EMG sensor or an accelerometer, the second sensor is a temperature sensor, and both the first and second sensors are used to monitor muscle or uterine contractions. In one embodiment, the first sensor is an EMG sensor, the second sensor is a temperature sensor, and a third sensor is provided that is an accelerometer, and the first, second and third sensors are used to monitor muscle or uterine contractions, respectively.
[0042] By providing different types of sensors that are used to detect different signals from the body but monitor the same type of fetal or maternal activity, the collection of data regarding pregnancy and / or delivery may be more accurate and / or reliable as described above in the aforementioned aspects.
[0043] The method may further include displaying information based on the types of signals obtained from the plurality of sensors. The display of the information may be presented on a display as a time-correlated plot of the signals. The display may be such that the amplitude of the plot changes similarly for corresponding types of fetal or maternal activity. For example, the display may be such that the resulting amplitude change of the plot for a first signal when a uterine contraction occurs is the same or similar to the resulting amplitude change of the plot for a second or further signal. The amplitude changes of the plot may be in the same direction. The amplitude changes of the plot may be within a factor of, for example, 4, 3, 2, or 1.5.
[0044] According to another aspect of the present disclosure, there is provided a method of monitoring pregnancy or labor that includes placing a monitoring device on the body including an electromyogram sensor including two or more EMG electrodes and one or more position sensors, monitoring fetal or maternal activity during pregnancy or labor using the EMG electrodes of the electromyogram sensor, and monitoring the relative positions of the two or more EMG electrodes during fetal or maternal activity using the one or more position sensors.
[0045] In any of the aspects described herein, placing the monitoring device on the body may include placing the monitoring device at the fundus of the abdomen. [Brief description of the drawings]
[0046] Embodiments of the present invention will now be described, by way of example only, with reference to the accompanying drawings, in which:
[0047] [Figure 1] FIG. 1 is a top view of an apparatus according to an embodiment of the present disclosure.
[0048] [Diagram 2] FIG. 2 is a front view of the device of FIG.
[0049] [Figure 3a] FIG. 3a is a bottom view of the device of FIG.
[0050] [Figure 3b] FIG. 3b is a bottom view of the device of FIG. 1, showing the EMG surface electrodes of the device.
[0051] [Figure 4a] FIG. 4a is a plot showing the pattern of signals over the period of a uterine contraction detected using the apparatus of FIG.
[0052] [Figure 4b] FIG. 4b is a plot showing the signal pattern with one electromyography (EMG) sensor connection poor or missing over the period of a uterine contraction detected using the device of FIG.
[0053] [Figure 4c] FIG. 4c is a plot showing the signal pattern over the period of a uterine contraction detected using the apparatus of FIG. 1 along with noise rejection to both EMG sensors.
[0054] [Diagram 5] FIG. 5 is a top view of an apparatus according to another embodiment of the present disclosure.
[0055] [Figure 6a] FIG. 6a is a bottom view of the device of FIG.
[0056] [Figure 6b] FIG. 6b is a bottom view of the device of FIG. 5, showing the EMG surface electrodes of the device.
[0057] [Figure 7]Figures 7a and 7b each show a simplified bottom view of the device of Figure 6b with the EMG electrodes in first and second positions respectively.
[0058] [Figure 8] 8a and 8b are schematic diagrams of various electronic components of the devices of FIGS. 1 and 5, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0059] 1, 2, 3a, and 3b show a pregnancy or labor monitoring apparatus 10 according to an embodiment of the present disclosure. Apparatus 10 includes a monitoring device 11 adapted to be placed on the body. Monitoring device 11 has a housing 12 that contains the electronic components of monitoring device 11. Housing 12 has a top surface 13 and a bottom surface 14. As best seen in FIG. 2, bottom surface 14 has a contoured portion 15 that substantially corresponds to the curvature of the maternal abdomen. Housing 12 is sealed to prevent the ingress of fluids.
[0060] The monitoring device 11 further comprises a plurality of sensors integrated therein. The plurality of sensors includes at least a first sensor configured to detect a first type of signal from the body indicative of fetal or maternal activity during pregnancy or labor, and a second sensor configured to detect a second type of signal from the body different from the first type of signal and also indicative of fetal or maternal activity during pregnancy or labor. The type of fetal or maternal activity monitored by the different sensors may be the same. Detecting the different types of signals allows accurate collection of data in the presence of fetal and / or maternal movement, interventions, and the pregnancy or labor process itself, as well as other environments that may result in missed or lost data. For example, even if one sensor is interrupted by non-contact, poor contact, or other external influences, the provision of other sensors allows the monitoring of at least one type of signal to continue continuously and uninterrupted. In the present disclosure, the monitoring device may be exposed to different conditions during monitoring, such as patient movement or exposure to water, which may result in one sensor being inappropriate for monitoring in a particular situation. However, because the monitoring device 11 detects at least two different types of signals, the loss or interruption of one sensor does not prevent continued monitoring of fetal or maternal activity, as useful signals remain detected by the other sensors.
[0061] In some embodiments, the first and second types of signals are both indicative of body movement during pregnancy or labor. Body movement may be, for example, fetal movement and / or maternal movement. Fetal activity may also include, for example, fetal posture and / or fetal heart rate. Maternal activity may also include, for example, muscle and uterine contractions, maternal posture, maternal heart rate and / or maternal temperature.
[0062] The first and second sensors may be any combination of two different sensors selected from the group including an electromyogram (EMG) sensor for detecting uterine contractions, a temperature sensor for detecting fetal and / or maternal body temperature, and an accelerometer for detecting fetal and / or maternal body position and movement. For example, the first sensor may be an EMG sensor and the second sensor may be a temperature sensor. In another alternative, the first sensor may be an EMG sensor and the second sensor may be an accelerometer. In yet another alternative, the first sensor may be a temperature sensor and the second sensor may be an accelerometer.
[0063] The monitoring device 11 may also include a third sensor for detecting a third type of signal from the body indicative of fetal or maternal activity during pregnancy or labor. In some embodiments, the third type of signal may be the same as the first type of signal or the second type of signal. In other embodiments, the third type of signal may be different from the first and second types of signals. The third sensor may be selected from a group including, for example, an accelerometer, a temperature sensor, an EMG sensor, and an ultrasound sensor.
[0064] The monitoring device 11 may also be configured with further sensors, e.g. a combination of four or more sensors, including at least two sensors configured to detect different types of signals. The further sensors may for example be selected from the group including accelerometers, temperature sensors, EMG sensors and ultrasonic sensors.
[0065] With reference to the embodiment shown in Fig. 3a, the monitoring device 11 includes four sensors, three of which are configured to detect different types of signals. In particular, the monitoring device 11 includes two EMG sensors 16, 17, a temperature sensor 18, and an accelerometer 101, all of which are integrated into the monitoring device 11. One of the three different sensors, such as one of the EMG sensors 16, 17, can be a first sensor configured to detect a first type of signal from the body indicative of fetal or maternal activity during pregnancy or labor. Another sensor, such as the temperature sensor 18 or the accelerometer 101, can be a second sensor configured to detect a second type of signal from the body that is different from the first type of signal but also indicative of fetal or maternal activity during pregnancy or labor.
[0066] Each of the EMG sensors 16, 17 includes a pair of contacts 16a, 16b, 17a, 17b disposed on the bottom surface 14 of the housing 12. The contacts 16a, 16b, 17a, 17b protrude from the bottom surface 14. The protrusions are such that the bottom surface 14 moves away from the body when the monitoring device 11 is placed on the body, which allows ventilation or airflow between the body and the monitoring device 11, improving patient comfort. The contacts 16a, 16b, 17a, 17b can be EMG electrodes. However, in this embodiment, the contacts 16a, 16b, 17a, 17b are also configured to receive and electrically couple to respective removable EMG surface electrodes 161a, 161b, 171a, 171b, as shown in FIG. 3b. The EMG surface electrodes 161a, 161b, 171a, 171b are configured to contact the skin. Through electrical contact with the skin, the EMG sensors 16, 17 are configured to detect changes in electrical potential (voltage) caused by uterine contractions or other fetal and / or maternal activity.
[0067] The accelerometer 101 is disposed within the housing 12 and configured to monitor maternal and / or fetal movement. The temperature sensor 18 is disposed on the bottom surface 14 of the housing 12 and configured to record fluctuations in maternal temperature. For example, the use of the temperature sensor 18 is used to identify fever due to infection. Additionally or alternatively, the temperature sensor 16 may also be used to detect signs and / or occurrence of uterine contractions. In this regard, the present disclosure recognizes that fluctuations in maternal temperature, particularly a change in body temperature from a baseline temperature, may be synonymous with the onset or occurrence of uterine contractions (as described below).
[0068] 4a-4c show examples of signals recorded over a period in which a patient is undergoing contractions using the monitoring device 11 and as displayed by the user interface. The plots show two signals 1001, 1002 detected from two EMG sensors 16, 17, a signal 1003 detected from a temperature sensor 18, and three signals 1004a, 1004b, 1004c detected along three different axes from an accelerometer 101, all of which are carried by the monitoring device 11. In the plots, the signals 1001-1004c are time correlated.
[0069] FIG. 4a shows that a repeating pattern of contractions (indicated by the letter "C") is identified in all three sensor types. It is recognized that fluctuations in maternal temperature (i.e., changes in body temperature from a reference temperature) may also be due to, for example, uterine contractions. In this example, an increase in body temperature may be due to, for example, uterine contractions, although other examples may also indicate other patterns of temperature changes. Thus, as described above, multiple sensors allow continuous monitoring of at least one type of signal indicative of fetal or maternal activity, such as uterine contractions, so that important data is not overlooked or lost during monitoring.
[0070] To allow the different plots of signals 1001-1004c to easily provide a user with indications of the same type of fetal or maternal activity, the scales of the plots are adjusted by the user interface such that the resulting amplitude changes of the plots for the different signals 1001-1004c are the same or similar when a uterine contraction occurs. For example, referring to FIG. 4a, the amplitude A1 of a contraction discernible in EMG signal plot 1001b is the same or similar to the amplitude A2 of a contraction discernible in temperature signal plot 1002.
[0071] The present disclosure is not necessarily limited to a hospital environment for a patient to monitor the occurrence of pregnancy or labor. Monitoring may be required when the patient is moving (e.g., walking, turning over, etc.) or when the patient is taking a shower or bath, for example, during pregnancy or labor. Thus, the multiple sensors of the monitoring device 11 may be exposed to different conditions during monitoring. Such conditions may result in the loss or interruption of one or more types of signals detected by the multiple sensors during monitoring. However, when the monitoring device 11 detects at least two different types of signals, the loss or interruption of one type of signal does not prevent the continuous monitoring of fetal or maternal activity, since the useful signal from the other sensor remains. This is evidenced, for example, by FIG. 4b, which shows that the substantial absence of signal 1001 due to poor or lost connection of one EMG sensor does not prevent the continuous monitoring of fetal or maternal activity, since the useful signal from the other sensor remains. Similarly, as can be seen from FIG. 4c, even if the signals 1001, 1002 from both EMG sensors are disturbed by noise, for example due to the EMG sensors being exposed to water, continuous monitoring of fetal or maternal activity is not missed or lost.
[0072] Referring again to Figures 1, 3a and 3b, the monitoring device 11 may also comprise at least one reference sensor 19 adapted to be placed on the body at a location away from the monitoring device 11 such that there is no fetal or maternal activity, which allows for filtering signals derived from other causes caused by maternal or fetal activity, such as physical movement (e.g., walking, rolling over, etc.) or normal temperature fluctuations, by referencing multiple sensors in the absence of fetal or maternal activity. In some embodiments, the at least one reference sensor 19 may be placed on the ribs. However, the at least one reference sensor 19 may be placed elsewhere on the body, such as the hip joint or sternum, or in other embodiments the reference sensor may be omitted.
[0073] In some embodiments, the at least one reference sensor 19 may include one or more of an EMG sensor, a temperature sensor, an accelerometer, and an ultrasonic sensor. In the embodiment shown in Figures 1, 3a and 3b, the reference sensor 19 may be an EMG sensor of the type described above to provide a reference for EMG readings from the EMG sensors 16, 17 of the monitoring device 11. The reference sensor may be wired to the monitoring device 11 or may be a physically separate wireless unit allowing for placement on a more remote part of the body. In this particular embodiment, the reference sensor 19 may have contacts 20 for receiving and electrically coupling a removable EMG surface reference electrode 191 as shown in Figure 3b. In this example, filtering of signals resulting from maternal or fetal activity may be performed by subtracting a signal derived from the reference sensor 19 from a signal derived from either the EMG sensors 16, 17 of the monitoring device 11.
[0074] 5, 6a and 6b show a pregnancy or delivery monitoring apparatus 21 according to another embodiment of the present disclosure. The apparatus 21 includes a monitoring device 22 adapted to be placed on the body. The monitoring device 22 has a central portion 24 and one or more flexible arm portions 25 connected to the central portion 24. Each of the one or more flexible arm portions 25 is configured to be independently operable with respect to the central portion 24 to facilitate placement of the monitoring device 22 on the body regardless of the curvature of the mother's abdomen and to bend and flex to accommodate deformations and movements of the body during wear. The monitoring device 22 also has a housing 23 in the central portion that houses the electronic components of the monitoring device 22. The housing 23 is sealed to prevent ingress of fluids, thereby preventing exposure of the electronic components of the monitoring device 22 to potentially harmful environmental factors, such as water and dust.
[0075] 5 and 6, the monitoring device 22 has four flexible arms 25a, 25b, 25c, 25d extending outward from the central portion 24 in a cross-arranged configuration. The flexible arms 25a, 25b, 25c, 25d have ends 26a, 26b, 26c, 26d with openings 27a, 27b, 27c, 27d. Adhesive seals 28a, 28b, 28c, 28d, which may be removable, are provided around the openings 27a, 27b, 27c, 27d, respectively, and are configured to adhere to the body to secure the monitoring device 22 to the body, forming a waterproof barrier around the openings 27a, 27b, 27c, 27d.
[0076] The monitoring device 22 also includes a number of sensors integrated therein, similar to those described above with respect to the apparatus 10. The number of sensors includes at least a first sensor configured to detect a first type of signal from the body indicative of fetal or maternal activity during pregnancy or labor, and a second sensor configured to detect a second type of signal from the body different from the first type of signal and also indicative of fetal or maternal activity during pregnancy or labor. The first and second sensors may be a combination of two different sensors selected from the group including an EMG sensor, a temperature sensor, and an accelerometer.
[0077] The monitoring device 22 may also include a third sensor for detecting a third type of signal from the body indicative of fetal or maternal activity during pregnancy or labor. In some embodiments, the third type of signal may be the same as the first type of signal or the second type of signal. In other embodiments, the third type of signal may be different from the first and second types of signals. The third sensor may be selected from a group including, for example, an accelerometer, a temperature sensor, an EMG sensor, and an ultrasound sensor.
[0078] The monitoring device 22 may also be configured with further sensors, e.g. a combination of four or more sensors including at least two sensors configured to detect different types of signals. The further sensors may for example be selected from the group including accelerometers, temperature sensors, EMG sensors and ultrasonic sensors.
[0079] With reference to the embodiment shown in Fig. 6a, the monitoring device 22 includes four sensors, three of which are configured to detect different types of signals. In particular, the monitoring device 22 includes two EMG sensors 29, 30, a temperature sensor 102 and an accelerometer 103, all of which are integrated in the monitoring device 22. One of the three different sensors, such as one of the EMG sensors 29, 30, can be a first sensor configured to detect a first type of signal from the body indicative of fetal or maternal activity during pregnancy or labor. Another sensor, such as the temperature sensor 102 or the accelerometer 103, can be a second sensor configured to detect a second type of signal from the body that is different from the first type of signal but also indicative of fetal or maternal activity during pregnancy or labor.
[0080] Each of the EMG sensors 29, 30 includes a pair of contacts 29a, 29b, 30a, 30b disposed at the ends 26a, 26b, 26c, 26d. Each of the contacts 29a, 29b, 30a, 30b can be an EMG electrode. However, in this embodiment, as shown in FIG. 6b, the contacts 29a, 29b, 30a, 30b are each configured to receive and electrically couple to a respective removable EMG surface electrode 291a, 291b, 301a, 301b. The EMG surface electrodes 291a, 291b, 301a, 301b are configured to contact the skin through the openings 27a, 27b, 27c, 27d. The EMG sensors 29, 30 through electrical contact with the skin are configured to detect electrical potential differences caused by uterine contractions.
[0081] An accelerometer 103 is disposed within central portion 24 and is configured to monitor maternal and / or fetal movement. A temperature sensor 102 is also disposed within central portion 24 and is configured to record fluctuations in maternal temperature in the same manner as described above with respect to device 10.
[0082] Also, in this embodiment, the monitoring device 22 includes flex sensors 104a, 104b, 104c, 104d, for example, disposed within the respective flexible arm portions 25a, 25b, 25c, 25d of the monitoring device 22. The flex sensors 104a, 104b, 104c, 104d may be configured to detect bending or flexing of the arm portions 25a, 25b, 25c, 25d. The bending or flexing or other or related deformations, such as extension and contraction of the arm portions 25a, 25b, 25c, 25d, may be caused by maternal movements, such as abdominal movements caused by the infant's movements, for example.
[0083] The flex sensor can be used as a position sensor that can monitor the relative position of two or more EMG electrodes by contacts 29a, 29b, 30a, 30b and / or EMG surface electrodes 291a, 291b, 301a, 301b connected to contacts 29a, 29b, 30a, 30b during fetal or maternal activity. Bending or deflection of arms 25a, 25b, 25c, 25d corresponds to the relative movement of the respective EMG electrodes. For example, the change in the relative position of the EMG electrodes when the EMG electrodes are fixed to the abdomen using adhesive seals 28a, 28b, 28c, 28d causes bending or flexion or other deformation of arms 25a, 25b, 25c, 25d. Bending or flexion or other deformation of arms indicates deformation of the body, for example, abdomen during fetal or maternal activity.
[0084] As an alternative to a flex sensor, a stretch sensor may be used. In general, any sensor in which the shape and / or dimensions of a structural part of the device are variable may be used as a position sensor, for example a monitoring device that detects changes in shape and / or dimensions that result in relative movement of EMG electrodes supported by the structure.
[0085] The central portion 24 may also be fixed for attachment to the abdomen. The central portion 24 may provide a reference location for the monitoring device, such as a center 241 of the central portion 24. Thus, the electrodes and the reference location may remain in fixed positions relative to the body.
[0086] The electrodes and central portion 24 may be fixed to the body, while the arms 25a, 25b, 25c, 25d therebetween are separate from the body.
[0087] By monitoring the position of the EMG electrodes during fetal or maternal activity, the EMG signals obtained from those electrodes can be interpreted in light of their relative positioning, allowing a more comprehensive analysis of the generated data, for example, it may be possible to correlate changes in the EMG signal with strains of the body in contact with the monitoring device, strains occurring as a result of contractions or other maternal or fetal activity.
[0088] The relative positions of the EMG electrodes can be determined based on trigonometric calculations. With reference to Fig. 7a, the length between the first EMG electrode 301a and the reference position 241 can be taken as the first side 401 of a conceptual triangle, the length between the second EMG electrode 301b and the reference position 241 can be taken as the second side of the conceptual triangle 402, and the length between the two electrodes 301a, 301b can be taken as the third side 403 of the conceptual triangle.
[0089] As the mother or fetus moves, for example as shown in Fig. 7b, the EMG electrodes 301a, 301b can move to new relative positions, which is reflected by the flexing or bending of the arms, i.e., a change in the geometry of the notional triangle 400', in this example increasing the length of the first side 40 of the triangle and decreasing the length of the second side 402' of the triangle.
[0090] The flexing or bending of the arms is sensed by flex sensors 104c, 104d which determine the distance between the electrodes 301a, 301b and the central portion 24 (i.e. the length of the first and second sides 401, 401', 402, 402 of the notional triangle 400, 400').
[0091] If the flexible arm is only flexible in the length direction, the angle α between the first and second sides 401, 401', 402, 402' may be a substantially constant angle and / or may be determined based on monitoring the deflection of the arm in more than one dimension. The third side 403, 403' of the notional triangle, i.e. the distance between the two electrodes 301a, 301b, may be calculated from knowledge of the lengths of the first and second sides 401, 401', 402, 402' and their relative angle α. However, other types of calculations may be performed to monitor electrode positions based on data from position sensors. Furthermore, relative positions may be determined between any combination of EMG electrodes 291a, 291b, 301a, 301b using the methods described. Position monitoring may be performed in real time in some embodiments and the signals shown in Figures 4a-4c may be directly correlated with signals from other sensors.
[0092] Referring again to FIG. 6a, the apparatus 21 may also comprise at least one reference sensor 31 coupled to the monitoring device 22, similar to that described for the apparatus 10. The at least one reference sensor 31 may be adapted to be placed on the body at a location away from the monitoring device 22 where there is no fetal or maternal activity, so as to provide a reference for the EMG readings and allow filtering of signals arising due to fetal or maternal activity from signals originating from other causes, such as whole body movements (e.g. walking, rolling over, etc.) and normal body temperature fluctuations. In some embodiments, the at least one reference sensor 31 may be placed on the ribs. However, it is understood that the at least one reference sensor 31 may be placed elsewhere on the body, such as the hip joint or sternum. The at least one reference sensor 31 is placed outside the housing of the monitoring device 22 and is movable relative to the housing. The at least one reference sensor 31 is connected via wires that maintain a physical and electrical connection between the reference sensor and other components of the monitoring device 22, but may be connected wirelessly in alternative embodiments.
[0093] In some embodiments, the reference sensor 31 may be an EMG sensor of the type described above with respect to the device 10. The reference sensor 31 may have contacts 32 for receiving and electrically coupling to a removable EMG surface reference electrode 311, as shown in Figure 6b.
[0094] In the embodiment shown in FIG. 6b, the reference sensor 31 may also be provided with an end 33 having an opening 34. An adhesive seal 35 may be provided around the opening 34. The adhesive seal 35 may be configured to adhere to the body to form a water-tight barrier around the opening 34. The EMG surface reference electrode 311 is configured to contact the skin through the opening 34. In this example, filtering of signals resulting from maternal or fetal activity may be done by subtracting a signal derived from the reference sensor 31 from a signal derived from either the EMG sensors 29, 30 of the monitoring device 22.
[0095] A monitoring device according to any of the above-mentioned embodiments may be adapted to be placed on the maternal abdomen, for example to be positioned over the fundus. The present disclosure recognizes that the area of maximum recordable maternal or fetal activity during contractions is beyond the fundus. However, it is understood that the monitoring device may be placed elsewhere on the body where useful monitoring of fetal or maternal activity may occur. The design and shape of the monitoring device may be suitable for placement in an appropriate location, for example, the maternal fundus, in a relatively intuitive and straightforward manner. The monitoring device may be configured for operation by multiple stakeholders, such as clinicians, patients, partners, or aid workers, and may be relatively easy to find and operate.
[0096] The apparatus according to any of the above embodiments may also include a user interface connected to the monitoring device, the user interface including a display for displaying information derived from signals detected by the multiple sensors. The user interface may comprise one or more of a desktop computer, a laptop computer, a smartphone, a personal digital assistant, a watch, a data collection band, and other similar devices configured to display information. The monitoring device may communicate with the user interface via a communication network such as the Internet, Wi-Fi, Bluetooth, etc. In some embodiments, the user interface may be remotely located so as to be accessible by a clinician. This allows for monitoring of the patient even in the absence of a clinician. Additionally or alternatively, the apparatus may comprise a user interface integrated into the monitoring device. For example, the user interface may be an on-board indicator. The user interface may provide an indication of the type of data being collected by the monitoring device and / or an indication of the attachment status of the device to the body, power level, etc.
[0097] A schematic diagram of the various electronic components of the device is shown in Fig. 8a. The operation of the electronic components may be applied to any of the device embodiments described above. However, in this particular embodiment, the schematic diagram of Fig. 8 is described with reference to the device 10 of Fig. 1. The monitoring device 11 may comprise a power source 400, e.g. a battery, for powering the electronic components of the monitoring device 11. The monitoring device 11 may also comprise a controller 401 (e.g. a microcontroller) connected to a number of sensors of the monitoring device 11. The number of sensors of the monitoring device 11 include two EMG sensors 16, 17, a temperature sensor 18, and an accelerometer 101. The device 10 also includes a reference sensor 19.
[0098] The controller 401 includes a processor 402 that receives signals from the plurality of sensors 16, 17, 18, 101 as well as the reference sensor 19 and stores the signals in a memory 403. The processor 402 may optionally filter the signals detected by the plurality of sensors 16, 17, 18, 101 based on the signals detected by the reference sensor 19. The transmitter 404 transmits, for example by wireless signals, information derived from the signals detected by the plurality of sensors 16, 17, 18, 101 and / or the reference sensor 19 to a user interface 405. A radio frequency signal or a Bluetooth signal or the like containing the information may be transmitted from the monitoring device 11 to the user interface 405. The user interface 405 includes a receiver 406 that receives information from the control unit 401 and a display 407 that displays the information. The information may be displayed in a format that is identifiable and assessable by a clinician to facilitate or assist in monitoring the pregnancy or delivery. Alternatively, the information may be displayed in an easier format for the patient to monitor their own pregnancy or delivery, without the presence of a clinician.
[0099] A further schematic diagram of the various electronic components is shown in Figure 8b. In this particular embodiment, the schematic diagram corresponds to the device 21 of Figure 5. From an electrical point of view, the device is substantially the same as the device 10 described with reference to Figure 8a. However, flex sensors 104a-d are further provided, which are connected to a controller that includes a controller 401', a processor 402', a memory 403' and a transmitter 404', which in turn is connected to a receiver 406'. and a user interface 405' including a display 407'. Referring to Figures 8a and 8b, the connections between the various components, including between the monitoring devices and the user interface, may be, for example, wired or wireless.
[0100] In general, any controller used in this disclosure may comprise several control or processing modules for receiving and processing signals derived from multiple sensors, and may include one or more storage devices for storing data such as the type of signal. The modules and storage devices may be implemented using one or more processing devices and one or more data storage units, and these modules and / or storage devices may be located in one location or distributed across multiple locations and may be interconnected by one or more communication links.
[0101] Further, the modules may be implemented by computer programs or program codes that include program instructions. The computer program instructions may include source code, object code, machine code, or other stored data operable to cause a controller to execute the described steps. The computer programs may be written in any form of programming language, including compiled or interpreted languages, and may be deployed in the form of stand-alone programs or including modules, components, subroutines, or other units suitable for use in a computing environment. The data storage may include suitable computer readable media, such as volatile (e.g., RAM) and / or non-volatile (e.g., ROM, disk) memory.
[0102] In any of the above embodiments, the apparatus may include one or more roving sensors to provide additional biodiagnostic and prognostic information about the pregnancy or labor. The roving sensors may be independent of the monitoring device. The roving sensors may include a fetal heart rate monitor to allow for determination of fetal distress during maternal contractions, a maternal heart rate monitor to provide an indication of the overall health of the mother during pregnancy or labor, and / or additional EMG sensors. The roving sensors may be coupled to the monitoring device and / or user interface via a wired or wireless connection.
[0103] The above-described embodiments have numerous advantages. For example, the multiple sensors provide continuous monitoring of at least one type of signal, ensuring that data is not missed or lost, thereby providing accurate collection of data. Additionally, the combination of sensors aids in assessing the status of pregnancy and labor, for example, distinguishing between false labor and the onset of labor, monitoring maternal health during pregnancy or labor, and / or monitoring fetal health before or during labor. Additionally, the embodiments allow the patient to operate the monitoring device without the need for the presence of a trained clinician, thereby enabling monitoring outside of a hospital environment.
[0104] It will be understood by those skilled in the art that numerous variations and / or modifications may be made to the above-described embodiments without departing from the broad general scope of the present disclosure, and the present embodiments are therefore considered in all respects to be illustrative and not restrictive.
Claims
1. a central portion and a plurality of flexible arms extending from the central portion, each of the flexible arms being operable relative to the central portion; an electromyogram sensor comprising two or more EMG electrodes for monitoring fetal or maternal activity during pregnancy or labor, each of said EMG electrodes being disposed at an end of a respective one of said flexible arms; An accelerometer; A monitoring device having A device for monitoring pregnancy or childbirth comprising:
2. The apparatus of claim 1 , wherein the monitoring device comprises at least four of the flexible arms arranged in a cross shape.
3. The device of claim 1 , wherein the electromyographic sensor comprises at least one electrical contact disposed at each end, the at least one electrical contact electrically coupling to an EMG surface electrode.
4. 10. The apparatus of claim 1, wherein the monitoring device comprises a housing having electronic components therein, the housing being a hermetic housing to prevent ingress of fluids.
5. The monitoring device comprises a housing having electronic components therein; the electromyographic sensor includes at least one electrical contact disposed on a bottom surface of the housing; 10. The apparatus of claim 1, wherein the at least one electrical contact is configured to electrically couple to an EMG surface electrode and configured to protrude from the bottom surface such that the bottom surface is away from the body when the monitoring device is placed on the body.
6. a central portion and a plurality of flexible arms extending from the central portion, each of the flexible arms being operable relative to the central portion; A temperature sensor; one or more position sensors disposed on the flexible arm; A monitoring device having A device for monitoring pregnancy or childbirth comprising:
7. The apparatus of claim 6 , wherein the one or more position sensors include one or more flex or stretch sensors that monitor flexure, bending or deformation of a portion of the monitoring device.
8. 7. The apparatus of claim 6, wherein the monitoring device comprises an electromyogram sensor comprising two or more EMG electrodes for monitoring fetal or maternal activity during pregnancy or labor, each EMG electrode being positioned at the end of a respective one of the flexible arms.
9. 10. The apparatus of claim 8, wherein the electromyographic sensor comprises at least one electrical contact disposed at each end portion, the at least one electrical contact configured to electrically couple an EMG surface electrode.
10. 7. The apparatus of claim 6, wherein the monitoring device comprises a housing having electronic components therein, the housing being a hermetic housing to prevent ingress of fluids.
11. a central portion and a plurality of flexible arms extending from the central portion, each of the flexible arms being operable relative to the central portion; An accelerometer; one or more position sensors disposed on the flexible arm; A monitoring device having A device for monitoring pregnancy or childbirth comprising:
12. The apparatus of claim 11 , wherein the one or more position sensors include one or more flex or stretch sensors that monitor flexure, bending or deformation of a portion of the monitoring device.
13. 12. The apparatus of claim 11, wherein the monitoring device comprises an electromyogram sensor comprising two or more EMG electrodes for monitoring fetal or maternal activity during pregnancy or labor, each EMG electrode being positioned at the end of a respective one of the flexible arms.
14. 14. The apparatus of claim 13, wherein the electromyographic sensor comprises at least one electrical contact disposed at each end portion, the at least one electrical contact configured to electrically couple an EMG surface electrode.
15. The monitoring device comprises a housing having electronic components therein; the electromyographic sensor includes at least one electrical contact disposed on a bottom surface of the housing; 14. The apparatus of claim 13, wherein the at least one electrical contact is configured to electrically couple to an EMG surface electrode and configured to protrude from the bottom surface such that the bottom surface is away from the body when the monitoring device is placed on the body.
16. A monitoring device for placement on the body and a number of sensors integrated into the monitoring device; The plurality of sensors includes at least a first sensor configured to detect a first type of signal from the body indicative of a first type of fetal or maternal activity during pregnancy or labor; a second sensor configured to detect a second type of signal from the body indicative of a first type of fetal or maternal activity during pregnancy or labor and distinct from the first type of signal; Including, the first sensor is a temperature sensor; the second sensor being an accelerometer; A device for monitoring pregnancy or childbirth.
17. 17. The apparatus of claim 16, wherein the monitoring device comprises a housing having electronic components therein, the housing having a top surface and a bottom surface contoured for placement on the body.
18. the monitoring device includes a central portion and one or more flexible arms extending from the central portion; each of the one or more flexible arms is configured to be manipulable relative to the central portion to facilitate placement of the monitoring device on the body; Each end of the flexible arm has an opening and an adhesive seal provided around the opening, the adhesive seal is configured to adhere to the body to secure the monitoring device to the body and to form a waterproof barrier around the opening; 20. The apparatus of claim 17.
19. at least one reference sensor adapted to be placed on the body at a location remote from the monitoring device to provide a reference value for the plurality of sensors in the absence of fetal or maternal activity; The reference sensor is connected to the monitoring device by wire or wirelessly.
17. The apparatus of claim 16.
20. A monitoring device for placement on the body and a number of sensors integrated into the monitoring device; The plurality of sensors includes at least a first sensor configured to detect a first type of signal from the body indicative of a first type of fetal or maternal activity during pregnancy or labor; a second sensor configured to detect a second type of signal from the body indicative of a first type of fetal or maternal activity during pregnancy or labor and distinct from the first type of signal; Including, The monitoring device comprises a housing having electronic components therein; The housing is a sealed housing to prevent fluid ingress. A device for monitoring pregnancy or childbirth.