The hemostatic system in pregnant women in relation to fetal sex

Objective. To study the specific features of the female hemostatic system at different stages of physiological pregnancy in relation to fetal sex. Subjects and methods. Examinations were made in 360 women with physiological pregnancy, including 187 pregnant women with male fetuses (Group 1) and 173 with female fetuses (Group 2) in the first, second, and third trimesters (a longitudinal study). Clinical, laboratory, biochemical, and instrumental studies were used. Results. There were statistically significant differences in blood coagulation parameters in the women at different stages of physiological pregnancy in relation to fetal sex: the mothers with second-trimester male pregnancy were found to have a more marked increase in D-dimer levels, soluble fibrin monomer complex index, and prothrombin time with a parallel decrease in prothrombin index than those with female pregnancy. In addition to the above-mentioned changes, there was a more pronounced rise in platelet counts and an increase in the number of significant strong and moderate correlations between the components of the hemostatic system in the third trimester whereas their largest number in female pregnancy mothers were recorded only in the first trimester of pregnancy. Conclusion. The findings suggest that the pregnant women with male fetuses have more pronounced activity of some components of the hemostatic system and their enhanced intrasystemic integration as pregnancy becomes longer whereas those with female fetuses show a predominance of intrasystemic integration processes in the coagulation system in early pregnancy.

physiological pregnancy, blood coagulation system, hemostatic parameters, fetal sex