Socio-biological factors of miscarriage

Socio-biological factors significantly affect the course of pregnancy and therefore may be associated with miscarriage. Many researchers link miscarriages to their place of residence. This indicator is particularly high among visiting women who are not adapted to the extreme conditions of the North. Women who live in these areas for less than 3 years, premature births and miscarriages are observed in 1,5-2 times more often than in local women and those who live in these regions for more than 3 years. The frequency of miscarriage is explained not only by the complexity of the processes of adaptation to new, more severe climatic conditions, but also by the difficulties of providing specialized assistance in remote areas.

Seasonal variability of premature termination of pregnancy was noted. In the autumn and spring months the frequency of this complication increases.

In industrial cities and large settlements, the frequency of miscarriages is statistically higher than in small settlements.

Working conditions have a certain effect on the course of pregnancy. When studying the impact of production factors, a direct dependence of premature termination of pregnancy on the mother's profession, the nature of work, on the presence of occupational hazards, even under the condition of light work during pregnancy, was established. Apparently, the impact of harmful working conditions (chemical hazards, vibration, radiation, etc.) significantly violates reproductive function and in the future can lead to miscarriage.

At present, about 56 teratogens are known to humans and the most significant of them are high doses of radiation, mercury and lead.

Studies conducted after the atomic bombings in Japan showed that many years later, there is an increased risk of birth of children with microcephaly, with a delay in the development of both mental and general in their offspring. Spontaneous abortions, premature births and stillbirths are still higher in this region than in the population.

But long-term exposure to low doses of radiation also adversely affects the reproductive function of women. As shown by research Sokur TN. (2001), in the regions affected by the Chernobyl accident, under conditions of constantly operating small doses of radiation, changes in the reproductive health indicators of women and their offspring are clearly revealed. The growth of spontaneous abortions in 2-3.5 times was noted, the frequency of the threat of interruption increased 2.5 times. In the areas of the greatest radiation contamination, the frequency of abortion was 24.7%.

Diagnostic X-ray examination in the first trimester of pregnancy does not have a teratogenic effect, if it is less than 5 rad (Creasy et al., 1994). Large doses (360-500 rad), used for therapeutic purposes, cause miscarriages in most cases. Non-ionizing reactions (microwaves, short waves) cause a thermal effect and can have an adverse effect on the fetus through hyperthermia. Even in large studies on the use of microwave and short-wave diathermy in pregnancy, pregnancy loss was the same as in the control group.

Heavy metal salts, such as mercury, lead can accumulate in the body, they penetrate the placenta to the fetus and can have adverse effects, especially on the development of the central nervous system. It is known from animal experiments that prolonged exposure to mercury salts even in small doses leads to miscarriage. In humans, mercury does not cause structural anomalies of development and is not always accompanied by miscarriage, but its effect on the neurological condition becomes evident only after birth.

The toxic effect of lead on pregnancy is known for more than 100 years. According to many researchers, the incidence of miscarriages among female workers associated with lead (printers) is many times higher than in the population (1991 SDS). Legislation in many countries does not allow women to work related to lead.

At present, there are a lot of works on the role of pesticides in complications of pregnancy, but there is no randomized data on the role of pesticides in interrupting pregnancy and, according to the latest data, they do not have a teratogenic effect.

Insecticides are mainly neurotoxic: in many agricultural areas, large studies of their role in reproductive losses have been carried out. According to most researchers, working with insecticides for more than 6 months leads to a significant increase in the frequency of miscarriage.

Premature births are more common among women engaged in manual labor, among young women, who combine work and study. Usual miscarriage is more common in women of intellectual labor. Among women who work more than 42 hours per week in the first trimester of pregnancy, the incidence of preterm delivery is 8.5%, while among women who work less than 42 hours per week - 4.5%. However, working women do not have an increased risk of spontaneous abortions, stillbirths and intrauterine growth retardation.

Among women who use several modes of transport on their way to work, premature birth is observed in 22%, with a lower load - in 6.3%. In women working standing, the rate of premature birth is 6.3%, with sedentary work - 4.3%.

Of the factors that affect the level of miscarriage, it should be noted the mother's age and parity. The contingent with miscarriage is mostly young, but older than among women giving birth on time, and is on average 29.8 ± 0.8 years against 25.7 + 0.1 years. Relatively low rates of preterm delivery are observed in women aged 20-24 and 25-29 years (7.1 and 7.4%, respectively).

Miscarriage of pregnancy is higher in women younger than 20 years and older than 35 years, in both cases it reaches 15.6%. There are conflicting data on the impact of parity on miscarriage. With the increase in the number of births, the frequency of preterm birth increases: at the second - 8.4%, with the third and subsequent - 9.2%. Other authors note a tendency to decrease the number of premature births with parity growth, believing that parental importance is more important, and the interval between births (the shorter it is, the more often complications arise). A certain pattern in the family, the amount of homework, the nature of the relationship between the spouses have a significant effect on the course and outcome of pregnancy. Among prematurely given birth a significant number of women were in unregistered marriage, as well as those who did not solve housing problems, or during pregnancy, there were stressful situations. The dependence of miscarriage on the weight of the mother and her nutrition during pregnancy is established.

Significant influence on the course of pregnancy is caused by bad habits, especially smoking, alcohol, drugs.

Smoking during pregnancy increases the frequency of miscarriages, the frequency of placental abruption, placenta previa, delayed fetal development, increases perinatal mortality. The effect of nicotine is dose-dependent: the more cigarettes are smoked per day, the higher the adverse effect on pregnancy.

Alcohol has a teratogenic effect on the fetus (alcoholic fetus syndrome), especially severe during pregnancy and fetal chronic alcoholism. He, like nicotine, is dose-dependent. Even average levels of alcohol use lead to an increase in miscarriages and premature births.

The frequency of spontaneous abortion among women who drink alcohol was 29%, perinatal mortality - 12-25%, premature birth - 22% and alcoholic syndrome in the fetus - 0.1-0.4%.

The combined effect of alcohol and smoking and drug use aggravates the unsuccessful outcomes of pregnancy. According to the authors, the effect of drugs can be secondary to alcohol and cigarettes.

Many researchers associate miscarriages with stressful situations. Others believe that stress is not directly related to spontaneous miscarriage, since the nature of stress and stress response is very individual. Pathophysiological mechanisms that could be responsible for miscarriage induced by stress reactions are difficult to identify. Stress can be associated with an increase in catecholamines, which as a result can cause a vasoconstrictor effect and lead to a disruption in the nutrition and respiration of the fetus. The role of the psychocytokine mechanism of pregnancy loss is possible.

The habitual loss of pregnancy is often accompanied by severe depression in women and severe emotional experiences in a married couple.

Thus, taking into account the significant influence of social factors during pregnancy, during dispensary observation of pregnant women, one should take into account not only the state of health, but also their social and hygienic characteristics and psychological situations.

[1], [2], [3], [4], [5], [6], [7]