Uterine contraction probe control circuit capable of measuring respiratory rate of pregnant woman

Abstract

The utility model provides a uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman, which comprises a pressure sensing signal acquisition circuit, a pressure sensing signal amplification circuit, a respiratory signal high-pass filter circuit, a uterine contraction signal low-pass filter circuit and an MCU (Microprogrammed Control Unit) signal processing module, the output end of the pressure sensing signal acquisition circuit is connected with the input end of the pressure sensing signal amplification circuit, and the output end of the pressure sensing signal amplification circuit is connected with the input end of the respiration signal high-pass filter circuit and the input end of the uterine contraction signal low-pass filter circuit. The output end of the respiration signal high-pass filter circuit and the output end of the uterine contraction signal low-pass filter circuit are connected with the input end of the MCU signal processing module, and the output end of the MCU signal processing module is connected with a display device. The uterine contraction probe has the advantages that one uterine contraction probe can measure uterine contraction parameters and respiratory frequency parameters of a pregnant woman at the same time.

Description

Technical Field

[0001] The utility model relates to the technical field of circuits, in particular to a uterine contraction probe control circuit capable of measuring the breathing frequency of pregnant women. Background Art

[0002] The respiratory rate of pregnant women is an important indicator for monitoring the health of pregnant women. During pregnancy, the respiratory rate of pregnant women may increase, which is usually due to physiological changes and the needs of fetal growth. The following are some of the meanings of changes in the respiratory rate of pregnant women:

[0003] 1. Physiological adaptation: The increase in the respiratory rate of pregnant women is a physiological adaptation to the increased metabolic needs of the fetus. As the uterus grows, the diaphragm rises, and the space for lung expansion is limited, so pregnant women may breathe more frequently to ensure adequate oxygen supply to the fetus and themselves.

[0004] 2. Fetal oxygen supply: The increase in breathing rate helps ensure that the pregnant woman and the fetus get enough oxygen. Oxygen is essential for the normal growth and development of the fetus.

[0005] 3. Health monitoring: Monitoring the respiratory rate of pregnant women can help identify potential health problems. For example, a too fast respiratory rate may be related to anemia, dehydration, or hypertensive diseases during pregnancy (such as preeclampsia).

[0006] 4. Adaptation during exercise: During exercise, pregnant women's breathing rate will increase to adapt to the increased metabolic needs. Pregnant women should avoid excessive fatigue and oxygen-poor environments such as plateaus to prevent themselves and the fetus from hypoxia.

[0007] 5. Signs of abnormal breathing: If a pregnant woman's breathing rate increases significantly, especially when she is resting, this may be a sign that there may be some kind of health problem. Pregnant women should consult a doctor for further evaluation and necessary treatment.

[0008] In short, the respiratory rate of pregnant women is an important health indicator that reflects the oxygen supply status of pregnant women and fetuses. Pregnant women should have regular prenatal check-ups and communicate with medical professionals in a timely manner if they have any health concerns.

[0009] At present, the respiratory parameters in fetal monitoring are obtained through the chest impedance method, that is, through the ECG electrodes attached to the chest, an alternating constant current source of a certain frequency is applied to the electrode end. When the human body breathes, the chest impedance changes, and the voltage at both ends of the electrode also changes accordingly. By detecting this change, the human respiratory rate can be obtained. However, this method requires the use of the chest impedance method to monitor the respiratory rate of pregnant women, which requires electrodes and an alternating constant current source, and the circuit is complex; and the electrodes are attached to the chest and used for a long time, which can easily cause discomfort to people, and it is complicated and cumbersome to use.

[0010] In addition, the contraction parameter detection in the fetal monitoring equipment is achieved through the contraction probe placed at the bottom of the uterus. The pressure strain gauge on the contraction probe senses the pressure changes acting on the strain gauge when the contraction occurs, so as to obtain the intensity, duration and periodicity of the contraction. When detecting contraction information, the contraction probe will detect breathing, which is manifested as a periodic fluctuation signal superimposed on the contraction curve that is much higher than the frequency of contractions. In a quiet state, the normal breathing rate of a normal person is 12-20cpm (times / minute), but we usually filter out this breathing as an interference signal and cannot detect the breathing rate synchronously. Utility Model Content

[0011] In order to solve the problems in the prior art, the utility model provides a uterine contraction probe control circuit that can measure the respiratory rate of pregnant women. By arranging a pressure sensor signal acquisition circuit, a pressure sensor signal amplification circuit, a respiratory signal high-pass filter circuit, a uterine contraction signal low-pass filter circuit and an MCU signal processing module that cooperate with each other in the uterine contraction probe, it can be achieved that a uterine contraction probe can simultaneously measure the uterine contraction parameters and respiratory rate parameters of the pregnant woman, which solves the problem in the prior art that the detection of the respiratory rate parameters of the pregnant woman is cumbersome and the uterine contraction probe can only measure the uterine contraction parameters.

[0012] The utility model provides a uterine contraction probe control circuit capable of measuring the respiratory frequency of a pregnant woman, comprising a pressure sensing signal acquisition circuit, a pressure sensing signal amplifying circuit, a respiratory signal high-pass filtering circuit, a uterine contraction signal low-pass filtering circuit and an MCU signal processing module, wherein the input end of the pressure sensing signal acquisition circuit is connected to a power supply, the output end of the pressure sensing signal acquisition circuit is connected to the input end of the pressure sensing signal amplifying circuit, the output end of the pressure sensing signal amplifying circuit is connected to the input end of the respiratory signal high-pass filtering circuit and the input end of the uterine contraction signal low-pass filtering circuit, the output end of the respiratory signal high-pass filtering circuit and the output end of the uterine contraction signal low-pass filtering circuit are connected to the input end of the MCU signal processing module, the output end of the MCU signal processing module is connected to a display device, the pressure sensing signal acquisition circuit can acquire a pressure change signal of the uterine fundus of the pregnant woman and output the signal to the MCU signal processing module after amplification by the pressure sensing signal amplifying circuit, screening of respiratory signal by the respiratory signal high-pass filtering circuit and screening of uterine contraction signal by the uterine contraction signal low-pass filtering circuit, and finally displaying the signal on the display device.

[0013] The utility model is further improved, and the pressure sensing signal acquisition circuit is provided with a bridge-type uterine contraction pressure sensor strain gauge R9, a bridge-type uterine contraction pressure sensor strain gauge R16, a resistor R1, a resistor R2, a resistor R11 and a capacitor C24, wherein one end of the bridge-type uterine contraction pressure sensor strain gauge R9 is connected to one end of the resistor R1 and the input end of the pressure sensing signal amplification circuit, one end of the bridge-type uterine contraction pressure sensor strain gauge R16 is connected to one end of the resistor R2 and the input end of the pressure sensing signal amplification circuit, the other end of the resistor R1 is connected to the other end of the resistor R2, one end of the resistor R11, and one end of the capacitor C24, the other end of the resistor R11 is connected to a power supply, and the other end of the bridge-type uterine contraction pressure sensor strain gauge R9, the other end of the bridge-type uterine contraction pressure sensor strain gauge R16, and the other end of the capacitor C24 are grounded.

[0014] The utility model is further improved, the pressure sensing signal amplification circuit is provided with an operational amplifier U1-A, an operational amplifier U1-B, an operational amplifier U4-A, a resistor R6, a resistor R7, a resistor R8, a resistor R10, a resistor R12, a resistor R13, a resistor R20 and a resistor R26, wherein one end of the resistor R6 is connected to one end of the bridge-type uterine contraction pressure sensor strain gauge R9, the other end of the resistor R6 is connected to the in-phase input end of the operational amplifier U1-B, the inverting input end of the operational amplifier U1-B is connected to one end of the resistor R8 and one end of the resistor R26, the output end of the operational amplifier U1-B is connected to one end of the resistor R12 and the other end of the resistor R26, the other end of the resistor R12 is connected to the resistor R2 0 and the inverting input terminal of the operational amplifier U4-A, one end of the resistor R7 is connected to one end of the bridge type uterine contraction pressure sensor strain gauge R16, the other end of the resistor R7 is connected to the non-inverting input terminal of the operational amplifier U1-A, the inverting input terminal of the operational amplifier U1-A is connected to the other end of the resistor R8 and one end of the resistor R10, the output end of the operational amplifier U1-A is connected to one end of the resistor R13 and the other end of the resistor R10, the other end of the resistor R13 is connected to the non-inverting input terminal of the operational amplifier U4-A, the output end of the operational amplifier U4-A is connected to the other end of the resistor R20, the input end of the respiratory signal high-pass filter circuit, and the input end of the uterine contraction signal low-pass filter circuit.

[0015] The utility model is further improved, and the pressure sensing signal amplifying circuit is further provided with capacitor C7, capacitor C9, capacitor C10 and resistor R15, wherein one end of the capacitor C7 is connected to the other end of the resistor R7, one end of the capacitor C10, and the in-phase input end of the operational amplifier U1-A, one end of the capacitor C9 is connected to the other end of the resistor R6, the other end of the capacitor C10, and the in-phase input end of the operational amplifier U1-B, one end of the resistor R15 is connected to the other end of the resistor R13 and the in-phase input end of the operational amplifier U4-A, and the other end of the resistor R15, the other end of the capacitor C7, and the other end of the capacitor C9 are grounded.

[0016] The utility model is further improved, the breathing signal high-pass filter circuit is provided with a capacitor C2, a resistor R3, an operational amplifier U4-B, a resistor R4 and a resistor R5, wherein one end of the capacitor C2 is connected to the output end of the operational amplifier U4-A, the other end of the capacitor C2 is connected to one end of the resistor R3 and the in-phase input end of the operational amplifier U4-B, the inverting input end of the operational amplifier U4-B is connected to the output end of the operational amplifier U4-B, one end of the resistor R4, one end of the resistor R5, and the input end of the MCU signal processing module, the other end of the resistor R4 is connected to a 3.3V bias voltage source, and the other end of the resistor R3 and the other end of the resistor R5 are grounded.

[0017] The utility model is further improved in that a capacitor C16 and a resistor R14 are provided in the contraction signal low-pass filter circuit, wherein one end of the resistor R14 is connected to the output end of the operational amplifier U4-A, the other end of the resistor R14 is connected to one end of the capacitor C16 and the input end of the MCU signal processing module, and the other end of the capacitor C16 is grounded.

[0018] The utility model is further improved in that the bridge-type uterine contraction pressure sensor strain gauge R9 and the bridge-type uterine contraction pressure sensor strain gauge R16 are both 0.1% low temperature drift resistors.

[0019] The utility model is further improved in that the MCU signal processing module is provided with an MCU microprocessor, and the model of the MCU microprocessor is GD32E103C8T6.

[0020] Compared with the prior art, the beneficial effects of the utility model are as follows: a uterine contraction probe control circuit capable of measuring the respiratory frequency of pregnant women is provided; by arranging a pressure sensing signal acquisition circuit, a pressure sensing signal amplifying circuit, a respiratory signal high-pass filtering circuit, a uterine contraction signal low-pass filtering circuit and an MCU signal processing module that cooperate with each other in the uterine contraction probe, the pressure sensing signal acquisition circuit can acquire the pressure change signal of the fundus of the pregnant woman's uterus and output it to the MCU signal processing module after amplification by the pressure sensing signal amplifying circuit, filtering of the respiratory signal by the respiratory signal high-pass filtering circuit and filtering of the uterine contraction signal by the uterine contraction signal low-pass filtering circuit, so as to calculate the respiratory frequency and uterine contraction data and finally display them on the display device; the pressure sensing signal can be acquired through the uterine contraction probe, and the uterine contraction signal and the pregnant woman's respiratory signal therein can be separated, so that one uterine contraction probe can simultaneously measure the uterine contraction parameters and respiratory frequency parameters of the pregnant woman, thereby solving the problem in the prior art that the detection of the pregnant woman's respiratory frequency parameters is cumbersome and the uterine contraction probe can only measure the uterine contraction parameters. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the solutions in the present application or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0022] Figure 1 This is a principle block diagram of a uterine contraction probe control circuit capable of measuring the respiratory frequency of pregnant women in the utility model;

[0023] Figure 2 The utility model discloses a circuit diagram of a uterine contraction probe control circuit capable of measuring the breathing frequency of a pregnant woman. DETAILED DESCRIPTION

[0024] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by technicians in the technical field of this application; the terms used in the specification of the application herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first", "second", etc. in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, not to describe a specific order.

[0025] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0026] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

[0027] like Figure 1-2As shown, the utility model provides a uterine contraction probe control circuit capable of measuring the breathing frequency of pregnant women, comprising a pressure sensing signal acquisition circuit, a pressure sensing signal amplifying circuit, a breathing signal high-pass filtering circuit, a uterine contraction signal low-pass filtering circuit and an MCU signal processing module, wherein the input end of the pressure sensing signal acquisition circuit is connected to a power supply, the output end of the pressure sensing signal acquisition circuit is connected to the input end of the pressure sensing signal amplifying circuit, the output end of the pressure sensing signal amplifying circuit is connected to the input end of the breathing signal high-pass filtering circuit and the input end of the uterine contraction signal low-pass filtering circuit, the output end of the breathing signal high-pass filtering circuit and the output end of the uterine contraction signal low-pass filtering circuit are connected to the input end of the MCU signal processing module, the output end of the MCU signal processing module is connected to a display device, and an MCU microprocessor is arranged in the MCU signal processing module, and the model of the MCU microprocessor is GD32E103C8T6. In this embodiment, the pressure sensing signal acquisition circuit can acquire the pressure change signal of the pregnant woman's uterine fundus and output it to the MCU signal processing module after amplification by the pressure sensing signal amplification circuit, filtering of the breathing signal by the breathing signal high-pass filtering circuit, and filtering of the contraction signal by the contraction signal low-pass filtering circuit, so as to calculate the breathing frequency and contraction data and finally display them on the display device. The pressure sensing signal can be acquired through the contraction probe, and the contraction signal and the pregnant woman's breathing signal can be separated, so that one contraction probe can simultaneously measure the contraction parameters and breathing frequency parameters of the pregnant woman. The human abdomen rises and falls with breathing, and the uterine contraction probe is fixed to the abdomen through a strap when monitoring. The principle of the uterine contraction probe is to produce voltage changes by squeezing the deformation of the probe bridge strain gauge through the uterine contraction pressure, and the uterine contraction parameters are calculated by amplifying the voltage changes. When detecting uterine contractions, the abdominal ups and downs caused by inhalation and exhalation will also squeeze the deformation of the probe bridge strain gauge to produce voltage changes. Therefore, the voltage changes produced by the deformation of the probe bridge strain gauge contain both uterine contraction signals and pregnant women's respiratory rate signals. The respiratory rate of pregnant women is 12-20cpm (times / minute). The frequency and intensity of uterine contractions will increase with the progress of labor. In the early stages of labor, uterine contractions may occur every 10 to 20 minutes, each lasting about 30 to 70 seconds. As labor progresses, the interval between uterine contractions may shorten to once every 5 to 10 minutes, and may last about 60 to 90 seconds. When uterine contractions become very frequent, occurring every 3 to 5 minutes, each lasting about 45 to 60 seconds, and the intensity continues to increase, it usually means that labor has entered the active phase. Therefore, it can be seen that the frequency of change of the probe strain gauge voltage signal corresponding to the pregnant woman's breathing frequency is greater than 0.15Hz, while the frequency of the probe strain gauge voltage signal corresponding to the uterine contraction change is much less than 0.15Hz, and the uterine contraction is almost close to the DC value. Therefore, in the circuit implementation, only high-pass circuit and low-pass circuit are needed to extract the uterine contraction signal and breathing signal respectively, and then send them to the MCU signal processing module for processing and calculation of the corresponding values.

[0028] like Figure 2 As shown, the pressure sensing signal acquisition circuit is provided with a bridge type uterine contraction pressure sensor strain gauge R9, a bridge type uterine contraction pressure sensor strain gauge R16, a resistor R1, a resistor R2, a resistor R11 and a capacitor C24, wherein one end of the bridge type uterine contraction pressure sensor strain gauge R9 is connected to one end of the resistor R1 and the input end of the pressure sensing signal amplification circuit, one end of the bridge type uterine contraction pressure sensor strain gauge R16 is connected to one end of the resistor R2 and the input end of the pressure sensing signal amplification circuit, the other end of the resistor R1 is connected to the other end of the resistor R2, one end of the resistor R11, and one end of the capacitor C24, the other end of the resistor R11 is connected to a power supply, the other end of the bridge type uterine contraction pressure sensor strain gauge R9, the other end of the bridge type uterine contraction pressure sensor strain gauge R16, and the other end of the capacitor C24 are grounded, and the bridge type uterine contraction pressure sensor strain gauge R9 and the bridge type uterine contraction pressure sensor strain gauge R16 are both 0.1% low temperature drift resistors. In this embodiment, the pressure sensing signal acquisition circuit is used to obtain the pressure sensing signal generated when the pregnant woman breathes and contracts.

[0029] like Figure 2As shown, the pressure sensing signal amplification circuit is provided with an operational amplifier U1-A, an operational amplifier U1-B, an operational amplifier U4-A, a resistor R6, a resistor R7, a resistor R8, a resistor R10, a resistor R12, a resistor R13, a resistor R20 and a resistor R26. One end of the resistor R6 is connected to one end of the bridge-type uterine contraction pressure sensor strain gauge R9, and the other end of the resistor R6 is connected to the non-inverting input end of the operational amplifier U1-B. The inverting input end of the operational amplifier U1-B is connected to one end of the resistor R8 and one end of the resistor R26. The output end of the operational amplifier U1-B is connected to one end of the resistor R12 and the other end of the resistor R26. The other end of the resistor R12 is connected to one end of the resistor R20 and the inverting input end of the operational amplifier U4-A. One end of the resistor R7 is connected to one end of the bridge-type uterine contraction pressure sensor strain gauge R16. The other end of the resistor R7 is connected to the non-inverting input end of the operational amplifier U1-A. The inverting input end of the operational amplifier U1-A is connected to the resistor R 8 and one end of resistor R10, the output end of operational amplifier U1-A is connected to one end of resistor R13 and the other end of resistor R10, the other end of resistor R13 is connected to the in-phase input end of operational amplifier U4-A, the output end of operational amplifier U4-A is connected to the other end of resistor R20, the input end of respiratory signal high-pass filter circuit and the input end of uterine contraction signal low-pass filter circuit; capacitor C7, capacitor C9, capacitor C10 and resistor R15 are also provided in the pressure sensing signal amplifying circuit, one end of capacitor C7 is connected to the other end of resistor R7, one end of capacitor C10 and the in-phase input end of operational amplifier U1-A, one end of capacitor C9 is connected to the other end of resistor R6, the other end of capacitor C10 and the in-phase input end of operational amplifier U1-B, one end of resistor R15 is connected to the other end of resistor R13 and the in-phase input end of operational amplifier U4-A, the other end of resistor R15, the other end of capacitor C7 and the other end of capacitor C9 are grounded. In this embodiment, the pressure sensing signal amplifying circuit is used to amplify the pressure sensing signal acquired by the pressure sensing signal acquiring circuit.

[0030] like Figure 2As shown, a capacitor C2, a resistor R3, an operational amplifier U4-B, a resistor R4 and a resistor R5 are provided in the breathing signal high-pass filter circuit, wherein one end of the capacitor C2 is connected to the output end of the operational amplifier U4-A, the other end of the capacitor C2 is connected to one end of the resistor R3 and the in-phase input end of the operational amplifier U4-B, the inverting input end of the operational amplifier U4-B is connected to the output end of the operational amplifier U4-B, one end of the resistor R4, one end of the resistor R5, and the input end of the MCU signal processing module, the other end of the resistor R4 is connected to a 3.3V bias voltage source, and the other end of the resistor R3 and the other end of the resistor R5 are grounded; a capacitor C16 and a resistor R14 are provided in the uterine contraction signal low-pass filter circuit, wherein one end of the resistor R14 is connected to the output end of the operational amplifier U4-A, the other end of the resistor R14 is connected to one end of the capacitor C16 and the input end of the MCU signal processing module, and the other end of the capacitor C16 is grounded. In this embodiment, changes in breathing and uterine contraction cause bending deformation of the bridge-type uterine contraction pressure sensor strain gauge R9 and the bridge-type uterine contraction pressure sensor strain gauge R16, wherein the installation positions of the bridge-type uterine contraction pressure sensor strain gauge R9 and the bridge-type uterine contraction pressure sensor strain gauge R16 are different, and the deformation is also different, which will cause one resistance to increase and the other resistance to decrease, thereby causing changes in the IN+ and IN- voltages. The voltage signal is amplified by the pressure sensing signal amplification circuit to obtain a pressure sensing signal mixed with breathing and uterine contraction. The pressure sensing signal is filtered by a high-pass filter (with the lowest cut-off frequency of 0.15Hz) composed of a resistor R3 and a capacitor C2 to extract a breathing signal. Since the high-pass filter obtains an AC signal, the MCU signal processing module cannot recognize a negative level, so the breathing signal extracted after the high-pass filter needs to be biased and then sent to the MCU signal processing module for processing to calculate the breathing frequency; the pressure sensing signal amplified by the pressure sensing signal amplifier circuit is also filtered by a low-pass filter (with the highest cut-off frequency of 0.15Hz) composed of a resistor R14 and a capacitor C16 to extract a contraction signal and send it to the MCU signal processing module for processing to calculate the corresponding contraction parameters, and finally displayed by the display device. In order to obtain higher signal acquisition accuracy, the bridge-type uterine contraction pressure sensor strain gauge R9 and the bridge-type uterine contraction pressure sensor strain gauge R16 in this embodiment are both 0.1% low-temperature drift resistors, so that the product monitoring accuracy is high and the product monitoring is stable.

[0031] As can be seen from the above, the utility model provides a uterine contraction probe control circuit capable of measuring the respiratory frequency of pregnant women. By arranging a pressure sensor signal acquisition circuit, a pressure sensor signal amplification circuit, a respiratory signal high-pass filter circuit, a uterine contraction signal low-pass filter circuit and an MCU signal processing module that cooperate with each other in the uterine contraction probe, the pressure sensor signal acquisition circuit can acquire the pressure change signal of the fundus of the pregnant woman's uterus and output it to the MCU signal processing module after amplification by the pressure sensor signal amplification circuit, filtering of the respiratory signal by the respiratory signal high-pass filter circuit, and filtering of the uterine contraction signal by the uterine contraction signal low-pass filter circuit, so as to calculate the respiratory frequency and uterine contraction data and finally display them on the display device. The pressure sensor signal can be acquired through the uterine contraction probe, and the uterine contraction signal and the pregnant woman's respiratory signal therein can be separated, so that one uterine contraction probe can simultaneously measure the uterine contraction parameters and respiratory frequency parameters of the pregnant woman, thereby solving the problem in the prior art that the detection of the pregnant woman's respiratory frequency parameters is cumbersome and the uterine contraction probe can only measure the uterine contraction parameters.

[0032] The specific implementation methods described above are preferred implementation methods of the present utility model, and are not intended to limit the specific implementation scope of the present utility model. The scope of the present utility model includes but is not limited to the specific implementation methods. All equivalent changes made in accordance with the present utility model are within the protection scope of the present utility model.

Claims

1. A uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman, characterized in that: It includes a pressure sensing signal acquisition circuit, a pressure sensing signal amplifying circuit, a breathing signal high-pass filtering circuit, a uterine contraction signal low-pass filtering circuit and an MCU signal processing module. The input end of the pressure sensing signal acquisition circuit is connected to a power supply, the output end of the pressure sensing signal acquisition circuit is connected to the input end of the pressure sensing signal amplifying circuit, the output end of the pressure sensing signal amplifying circuit is connected to the input end of the breathing signal high-pass filtering circuit and the input end of the uterine contraction signal low-pass filtering circuit, the output end of the breathing signal high-pass filtering circuit and the output end of the uterine contraction signal low-pass filtering circuit are connected to the input end of the MCU signal processing module, the output end of the MCU signal processing module is connected to a display device, the pressure sensing signal acquisition circuit can acquire the pressure change signal of the pregnant woman's uterine fundus and output it to the MCU signal processing module after amplification by the pressure sensing signal amplifying circuit, filtering of breathing signal by the breathing signal high-pass filtering circuit and filtering of uterine contraction signal by the uterine contraction signal low-pass filtering circuit for processing and calculating of breathing frequency and uterine contraction data, which are finally displayed on the display device.

2. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 1, characterized in that: The pressure sensing signal acquisition circuit is provided with a bridge-type uterine contraction pressure sensor strain gauge R9, a bridge-type uterine contraction pressure sensor strain gauge R16, a resistor R1, a resistor R2, a resistor R11 and a capacitor C24, wherein one end of the bridge-type uterine contraction pressure sensor strain gauge R9 is connected to one end of the resistor R1 and the input end of the pressure sensing signal amplification circuit, one end of the bridge-type uterine contraction pressure sensor strain gauge R16 is connected to one end of the resistor R2 and the input end of the pressure sensing signal amplification circuit, the other end of the resistor R1 is connected to the other end of the resistor R2, one end of the resistor R11, and one end of the capacitor C24, the other end of the resistor R11 is connected to a power supply, and the other end of the bridge-type uterine contraction pressure sensor strain gauge R9, the other end of the bridge-type uterine contraction pressure sensor strain gauge R16, and the other end of the capacitor C24 are grounded.

3. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 2, characterized in that: The pressure sensing signal amplifying circuit is provided with an operational amplifier U1-A, an operational amplifier U1-B, an operational amplifier U4-A, a resistor R6, a resistor R7, a resistor R8, a resistor R10, a resistor R12, a resistor R13, a resistor R20 and a resistor R26, wherein one end of the resistor R6 is connected to one end of the bridge-type uterine contraction pressure sensor strain gauge R9, the other end of the resistor R6 is connected to the in-phase input end of the operational amplifier U1-B, the inverting input end of the operational amplifier U1-B is connected to one end of the resistor R8 and one end of the resistor R26, the output end of the operational amplifier U1-B is connected to one end of the resistor R12 and the other end of the resistor R26, the other end of the resistor R12 is connected to one end of the resistor R20 and the other end of the resistor R26. The inverting input terminal of the operational amplifier U4-A is connected, one end of the resistor R7 is connected to one end of the bridge-type uterine contraction pressure sensor strain gauge R16, the other end of the resistor R7 is connected to the non-inverting input terminal of the operational amplifier U1-A, the inverting input terminal of the operational amplifier U1-A is connected to the other end of the resistor R8 and one end of the resistor R10, the output terminal of the operational amplifier U1-A is connected to one end of the resistor R13 and the other end of the resistor R10, the other end of the resistor R13 is connected to the non-inverting input terminal of the operational amplifier U4-A, the output terminal of the operational amplifier U4-A is connected to the other end of the resistor R20, the input terminal of the respiratory signal high-pass filter circuit, and the input terminal of the uterine contraction signal low-pass filter circuit.

4. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 3, characterized in that: The pressure sensing signal amplifying circuit is also provided with capacitor C7, capacitor C9, capacitor C10 and resistor R15, wherein one end of the capacitor C7 is connected to the other end of the resistor R7, one end of the capacitor C10, and the non-inverting input end of the operational amplifier U1-A, one end of the capacitor C9 is connected to the other end of the resistor R6, the other end of the capacitor C10, and the non-inverting input end of the operational amplifier U1-B, one end of the resistor R15 is connected to the other end of the resistor R13 and the non-inverting input end of the operational amplifier U4-A, and the other end of the resistor R15, the other end of the capacitor C7, and the other end of the capacitor C9 are grounded.

5. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 4, characterized in that: The breathing signal high-pass filter circuit is provided with a capacitor C2, a resistor R3, an operational amplifier U4-B, a resistor R4 and a resistor R5, wherein one end of the capacitor C2 is connected to the output end of the operational amplifier U4-A, the other end of the capacitor C2 is connected to one end of the resistor R3 and the in-phase input end of the operational amplifier U4-B, the inverting input end of the operational amplifier U4-B is connected to the output end of the operational amplifier U4-B, one end of the resistor R4, one end of the resistor R5, and the input end of the MCU signal processing module, the other end of the resistor R4 is connected to a 3.3V bias voltage source, and the other end of the resistor R3 and the other end of the resistor R5 are grounded.

6. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 5, characterized in that: The contraction signal low-pass filter circuit is provided with a capacitor C16 and a resistor R14, wherein one end of the resistor R14 is connected to the output end of the operational amplifier U4-A, the other end of the resistor R14 is connected to one end of the capacitor C16 and the input end of the MCU signal processing module, and the other end of the capacitor C16 is grounded.

7. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 6, characterized in that: The bridge-type uterine contraction pressure sensor strain gauge R9 and the bridge-type uterine contraction pressure sensor strain gauge R16 are both 0.1% low temperature drift resistors.

8. The uterine contraction probe control circuit capable of measuring the respiratory rate of a pregnant woman according to claim 7, characterized in that: The MCU signal processing module is provided with an MCU microprocessor, and the model of the MCU microprocessor is GD32E103C8T6.

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