Diagnostic tests to assess the course of pregnancy

Determination of basal temperature in the first 12 weeks of pregnancy. With a favorable course of pregnancy, the basal temperature is increased to 37.2-37.4 ° C. The temperature below 37 ° С with the differences indicates an unfavorable course of pregnancy. The possibilities of this test are very limited, since with undeveloped pregnancy, with anembrion, the temperature remains elevated while the trophoblast lives.

Cytological examination of the vaginal discharge is rarely taken into account, as among women with miscarriage, many infected with phenomena of cervicitis, vaginosis, in which the study is not informative, in the absence of infection, this test can be used. Before the 12th week of pregnancy, the cytological picture of the vaginal smear corresponds to the luteal phase of the cycle and the karyopic index (CPI) does not exceed 10%, at 13-16 weeks it is 3-9%. Up to 39 weeks, the KPI level remains within 5%. When there are signs of a threat of interruption, along with an increase in CPI in the smears, red blood cells appear, indicating an increase in the level of estrogens, an imbalance of progesterone-estrogenic relationships, and the appearance of micro-layers of the chorion or placenta.

A great prognostic value for estimating the course of pregnancy in the first trimester has a dynamic definition of the level of chorionic gonadotropin. It is determined in the urine or in the blood at the 3rd week of pregnancy. Its content rises in urine from 2500-5000 units in 5 weeks to 80,000 units at 7-9 weeks, decreases to 10,000-20,000 units at 12-13 weeks and at this level it remains to 34-35 weeks, then it rises slightly , but the significance of this rise is not clear.

Since the chorionic gonadotropin is produced by the trophoblast, a violation of its function, detachment, dystrophic, generative changes lead to a decrease in the level of excretion of the chorionic gonadotropin. To estimate the course of pregnancy, it is important not only the magnitude of the chorionic gonadotropin, but also the ratio of the peak of the chorionic gonadotropin to the gestation period. Too early appearance of the peak of the chorionic gonadotropin in 5-6 weeks, as well as the late appearance in 10-12 weeks and even more the absence of the peak of the chorionic gonadotropin testifies to the violation of the function of the trophoblast, and hence the yellow body of the pregnancy, whose function supports and stimulates the chorionic gonadotropin .

It should be noted that the early appearance of chorionic gonadotropin and its high level can be with multiple pregnancies. With undeveloped pregnancy, the chorionic gonadotropin is sometimes preserved at a high level, despite the death of the embryo. This is due to the fact that the rest of the trophoblast produces chorionic gonadotropin, despite the death of the embryo. Termination of pregnancy in the first trimester in most cases is the result of the insolvency of the trophoblast as an endocrine gland.

To assess the course of pregnancy, such an evaluation of trophoblast function as the determination of placental lactogen in the blood plasma can be used. True, it is often presented in scientific studies to confirm or deny the formation of placental insufficiency, than in clinical practice. Placental lactogen is determined from 5 weeks of pregnancy, and its level is constantly increasing until the end of pregnancy. With dynamic control of the level of placental lactogen, the lack of growth or decrease in its production is an unfavorable sign.

In the first trimester of pregnancy, the levels of estradiol and estriol are of great prognostic and diagnostic value.

The decrease in the level of estradiol in the first trimester, estriol in the II-III trimesters testifies to the development of placental insufficiency. True, in recent years this test is given less importance and is used mainly to assess placental insufficiency by the ultrasound and dopplerometry of the placenta and utero-placental blood flow, since it is believed that the decrease in estriol may be due to the decrease in the processes of aromatization in the placenta and not suffering the fetus.

There is a decrease in the production of estriol when taking glucocorticoids.

In women with hyperandrogenia to monitor the course of pregnancy and assess the effectiveness of glucocorticoid therapy, a large role is played by the determination of the 17C content in daily urine. Each laboratory has its own standards for the level of 17KS, with which it is necessary to compare the obtained data. It is necessary to remind patients about the rules of collecting daily urine, the need for a diet without dyeing red-orange products for 3 days before the collection of urine. In uncomplicated pregnancy there are no significant fluctuations in the voxecretion of 17KS, depending on the period of pregnancy. In the norm there are fluctuations from 20.0 to 42.0 nmol / l (6-12 mg / day). Simultaneously with the study of 17KS it is expedient to determine the content of dehydroepiandrosterone. Normally, the level of DEA is 10% excretion of 17KS. During pregnancy there are no significant fluctuations in the level of 17KS and DEA. An increase in the content of 17KS and DEA in urine or 17OP and DEA-S in the blood testifies to hyperandrogenism and the need for treatment with glucocorticoids. In the absence of adequate therapy, the development of pregnancy is disrupted most often as a type of undeveloped pregnancy; in the II and III trimesters fetal death is possible.

Prenatal diagnostics is an extremely important aspect of working with patients with habitual miscarriage. In the first trimester at 9 weeks, a chorion biopsy can be performed to determine the fetal karyotype to exclude chromosomal pathology. In the second trimester, in order to exclude Down's disease (if no first trimester trial has been performed), it is recommended that all pregnant women with the usual pregnancy loss have a history of chorionic gonadotropin, estradiol and alpha-fetoprotein levels in the mother's blood. Studies are conducted at 17-18 weeks. The increase in chorionic gonadotropin is higher than the normative parameters for this period, the decrease in estradiol and alpha-fetoprotein is suspicious for Down's disease in the fetus. With these indicators, all women, and after 35 years, regardless of the parameters obtained, it is necessary to hold an amniocentesis with a karyotypic evaluation of the fetus. In addition to this analysis in all hyperandrogenia and a history of anamnesis in case of suspicion of adrenogenital syndrome (in the presence of spouses in the HLAB14, B35-B18 system in possible carriers of the adrenogenital syndrome gene in the family), we perform a study of the levels of 17-hydroxyprogesterone in the blood. With this increase in the blood, amniocentesis is performed and the level of 17OP in the amniotic fluid is determined. Elevated levels of 17OP in the amniotic fluid indicate the presence of adrenogenital syndrome in the fetus.

The most informative test in assessing the course of pregnancy, the state of the embryo, fetus, placenta is ultrasound. In most cases, ultrasound can detect pregnancy from 3 weeks and indicate the localization of pregnancy in the uterus or outside it. The fetal egg at this time is a round, free from echostructure, formation located in the upper or middle third of the uterine cavity. At 4 weeks of gestation, it is possible to identify contours of the embryo. The increase in the uterus according to ultrasound begins with the 5th week, the formation of the placenta - from 6-7 weeks. Valuable information about the nature of the course of pregnancy can be obtained by measuring the uterus, fetal egg, embryo. Simultaneous determination of the size of the uterus and fetal egg allows to reveal some pathological conditions. With normal size of the fetal egg, there is a decrease in the size of the uterus when it is hypoplastic. The increase in the size of the uterus is observed with uterine myoma. In the early stages of pregnancy, multiple pregnancy is determined. Based on the size and condition of the yolk sac, it is possible to judge how pregnancy proceeds in its early stages. Echography is one of the most important methods of diagnosing an undeveloped pregnancy. The fuzziness of the contours and the decrease in the size of the fetal egg are determined, the embryo is not visualized, there is no cardiac activity and motor activity.

However, it can not be based on a single study, especially in the early stages of pregnancy, dynamic control is necessary. If these data are confirmed during repeated studies, the diagnosis of an undeveloped pregnancy is reliable.

In later terms, there may be signs of a threat of interruption in the condition of the myometrium.

Often, in the presence of bloody discharge, placental detachment areas are identified, the appearance of echo-negative spaces between the uterine wall and the placenta, indicating the accumulation of blood.

Malformations of the uterus during pregnancy are revealed better than outside it. Isthmiko-cervical failure is diagnosed if there is already a change in the cervix and prolapse of the bladder.

An extremely important aspect of ultrasound is the detection of malformations of the fetus. Identification of features of the placenta condition, localization, size, presence or absence of placental phenomena, structural abnormalities, presence or absence of placental edema, heart attacks, placenta maturity, etc.

Amount of amniotic fluid: polyhydramnios may be due to malformations of the fetus and infection; hypochlorism is a sign of placental insufficiency. An extremely important aspect is the presence of placental abruption, retrochoric hematomas, the phenomenon of "migration" of the placenta.

An extremely important method for assessing the fetus is the evaluation of the dopplerometric method of uteroplacental and fetoplacental blood flow, its compliance with gestational age. Studies are conducted from 20-24 weeks of pregnancy with an interval of 2-4 weeks, depending on the condition of the fetus. The spectra of the blood flow velocity curves of the left and right uterine arteries, the umbilical artery and the middle cerebral artery of the fetus are recorded. The evaluation of the blood flow velocity curves is performed by analyzing the maximum systolic (MSSC) and the end diastolic blood flow velocities (KDBC) with calculation of the angle-independent parameters: systolic-diastolic ratio, resistance index (IR) according to the formula:

IR = MSSC - KDSC / UWSC

, where the index (IR) is an informative indicator characterizing the peripheral resistance of the vascular system under study.

Cardiotocography - monitoring monitoring of the fetus is performed starting from 34 weeks of pregnancy with an interval of 1-2 weeks (according to indications).

Analysis of contractile activity of the uterus can be performed on a cardiac monitor, since the CTG recording can be simultaneously performed with the recording of the contractile activity of the uterus, and can also be performed by hysterography and tonusometry.

Hysterograms are recorded on a one- or three-channel dynamoterograph. To quantify the hysterograms in the instrument, a calibration device is provided, whose signal corresponds to 15 g / cm ². Registration is carried out in the position of the pregnant woman on her back. On the anterior abdominal wall in the area of the uterine body, using a belt, fix the sensor of the device. The duration of a separate study is 15-20 minutes. Hysterograms are processed by methods of qualitative and quantitative analysis, taking into account the duration, frequency, and amplitude of an individual reduction.

Tonometry - uses a tone meter developed by Hasin A.Z. Et al. (1977). The device is made in the form of two cylinders of different diameters. The larger cylinder is hollow. The second cylinder is smaller, the reference mass is located inside the first and can move relative to it. The degree of movement of the movable cylinder depends on the compliance of the support on which it is mounted and the area of the end part of the inner cylinder. The depth of immersion of the movable cylinder in the underlying substrate is marked on the measuring scale of the tonus meter and is expressed in conventional units. The measurement is made in the position of a woman lying on her back. The device is placed along the midline of the abdomen on the anterior abdominal wall in the projection area of the uterus. The tone of the uterus is measured in conventional units. With a tone of up to 7.5 cu. The tone of the uterus is considered normal, and more than 7.5 cu. Regarded as an increase in the basal tone of the uterus.

Of course, an experienced clinician with palpation of the uterus can tell whether it is in the tone or not, but when determining the effectiveness of different therapies, when evaluating different observation groups, not the clinical conclusions but accurate digital reflection of the process are needed, therefore this method of evaluation is very convenient, especially in the conditions of female consultations.

Other research methods needed to assess the course of pregnancy: assessment of hemostasiograms, virologic, bacteriological study, assessment of immune status are conducted in the same way as in pre-pregnancy studies.

Daily monitoring of arterial pressure. Hemodynamic disorders contribute to complications of pregnancy. Arterial hypertension is registered in 5-10% of pregnant women. Arterial hypotension occurs from 4.4% to 32.7% of pregnant women. Excessive reduction in blood pressure leads to hypoperfusion of the myocardium, brain, skeletal muscles, which often contributes to such complications as dizziness, fainting, weakness, fatigue, etc. Long-term hypertension, as well as hypotension, adversely affects the course of pregnancy. The method of daily monitoring of arterial pressure (BPD) in pregnant women allows more accurate than just a single determination of blood pressure, determine hemodynamic parameters.

The device for SMAT is a portable sensor, weighing about 390 g (along with batteries), which is attached to the waist of the patient, is connected to the shoulder cuff. Before starting the measurement, the device must be programmed with a computer program (ie, make the necessary intervals for measuring blood pressure, sleep time). The standard method of SMAD involves measuring blood pressure within 24 hours with 15-minute intervals in the afternoon and 30 minutes at night. Patients at the same time fill in a diary of monitoring, which notes the time and duration of periods of physical and mental activity and rest, the time of going to bed and awakening, the moments of meals and medications, the appearance and cessation of various changes in well-being. These data are necessary for the subsequent interpretation by the doctor of the data of SMAD. After the 24-hour measurement cycle is completed, the data is transferred via the interface cable to the personal computer for subsequent analysis, displaying the results on the monitor or printer and storing them in the database.

The following quantitative indicators are analyzed in the course of SMAD:

1. Average arithmetic indices of systolic, diastolic, mean arterial pressure and pulse rate (mmHg, bpm).
2. The maximum and minimum values of blood pressure in different periods of the day (mmHg).
3. Temporary hypertensive index is the percentage of the monitoring time during which the blood pressure level was higher than the specified parameters (%).
4. The temporal hypotonic index is the percentage of the monitoring time during which the blood pressure level was below the specified parameters (%). Normally, the time indices should not exceed 25%.
5. The daily index (the ratio of the average daily to the average) or the degree of nocturnal decrease in blood pressure and pulse rate is the difference between the average daily and average indicators, expressed in absolute figures (or in% of the average daily figures). For a normal circadian rhythm of blood pressure and pulse rate, there is at least a 10% decrease in sleep and a daily index of 1.1. Decrease in this indicator is usually inherent in chronic renal failure, hypertension of renal, endocrine origin, hypertension in pregnancy and preeclampsia. Inversion of the daily index (its negative value) is revealed in the most severe clinical variants of pathology.

The hypotension area index is the area bounded from below by the graph of pressure versus time, and from the top by the line of threshold values of arterial pressure.

The variability of SBP, DBP and heart rate, assessed more often by the standard deviation from the mean. These indicators characterize the degree of damage to target organs in cases of hemodynamic disorders.

Daily monitoring of arterial pressure in the obstetric clinic has a high diagnostic and prognostic significance. Based on the results of the applied monitoring of arterial pressure in the miscarriage clinic, the following conclusion can be drawn:

1. Daily monitoring of blood pressure in pregnant women allows much more informative than with occasional measurements, to identify and assess the severity of arterial hypotension and hypertension.
2. Almost half of patients with miscarriage (45%) have hypotension not only in the early stages, but also throughout the period of pregnancy.
3. Despite the fact that recently in the world literature the problem of hypotension as a pathological state is debated and there is no definitive definitive opinion on its nature, the adverse effect of hypotension on the course of pregnancy and the state of the intrauterine fetus is obvious. We have identified a close relationship between hypotension and the presence of placental insufficiency in patients with miscarriage in the anamnesis, and in the presence of severe hypotension there is also a more pronounced suffering of the fetus, which is confirmed by objective methods of functional diagnostics.
4. All pregnant women have a "white coat effect", masking the true level of blood pressure, leading to erroneous diagnosis of hypertension and to unjustified hypotensive therapy, further exacerbating the condition of the patient and the fetus.
5. Repeated monitoring of blood pressure during the course of pregnancy will allow timely detection of not only initial signs of changes in blood pressure in patients, but also improve the quality of diagnosis of placental insufficiency and intrauterine fetal suffering.
6. Further study of the course of pregnancy, the condition of the patient and fetus using this method will allow us to go deeper into the issues of the pathogenesis of arterial hypertension, hypotension in pregnancy, placental insufficiency. Daily monitoring of blood pressure during pregnancy is not only diagnostic and prognostic, but also therapeutic value, because allows to determine individual therapeutic tactics, its effectiveness, thereby reducing the frequency of complications of pregnancy and improving the outcome of labor for the fetus.

[1], [2], [3], [4], [5], [6]