Influence of meteorological factors on the day of birth on the number of births in Barnaul

The theories developed to explain the beginning of labor are usually considered outside the possible exogenous influence. In the literature, there are prerequisites for the study of the impact of meteorological factors on the initiation of delivery. The paper presents data on the dependence of the birth rate on meteorological environmental factors (atmospheric pressure, its gradient, temperature and humidity, wind speed) in a temperate continental climate of Western Siberia (Barnaul). The data recorded during 1998 (1,154 data) and within the climatic seasons are analyzed. For the purpose of verification of the received regularities, the repeated analysis is carried out on the material of data of 2014 (2145 data) on the basis that unlike a number of years which divided 1998 and 2014, environmental factors were the closest and typical for Barnaul climate. Conclusions were made on the results of the two replications based on these 1998 and 2014. With the help of dispersion analysis, it is shown that the key factor affecting the rate of delivery is the daily drop in atmospheric pressure in the direction of its reduction. Peculiarities of influence of meteorological factors on the frequency of births in different climatic seasons of the year. In particular, it was found that in the winter climatic period the number of births is most affected by meteorological factors, which include air temperature, atmospheric pressure, baric trend, air humidity. Possible mechanisms of observed phenomena are analyzed. It is assumed that one of the possible mechanisms of influence on the initiation of labor can be stressful corticotrophin-releasing secretion of hypothalamic factors, which, connected to the placental hormone, which is considered the "molecular clock" of pregnancy, its concentration increases and exceeds a certain threshold acts as a trigger to run the process of delivery ( Stefano et al., 2015). The second, the most probable factor influencing childbirth may be short-term changes in atmospheric pressure: it is possible the direct mechanical action of external barometric shifts on the volume of internal closed air-containing cavities, in particular, gas bubbles in the intestine, the swelling of which, when the atmospheric pressure decreases, can increase the pressure in the fetal bubble.