Sex hormones, hemostasis and early pregnancy loss

This study was designed to determine the association between coagulation factors and spontaneous abortion adjusting for sex steroids and to examine the influence of sex hormones on coagulation factors early in pregnancy.

Pregnant women presenting to the emergency department at the Hospital of the University of Pennsylvania were recruited and followed through 22 weeks gestation. Cases were women who experienced a spontaneous abortion (n=29) and controls were women who maintained their pregnancy to 22 weeks gestation (n=89). Participants completed a baseline questionnaire to assess demographic, reproductive, and drug use information. Blood samples measured estradiol, progesterone, fibrinogen, and factor VII antigen.

Cases of spontaneous abortion had significantly lower levels of estradiol, progesterone, fibrinogen and factor VII antigen compared to controls. The relationship between low levels of fibrinogen and factor VII antigen was diminished adjusting for the sex steroids. Regression analyses found low progesterone was the primary prospective marker for early pregnancy loss among our study population.

The relationship between coagulation factors and spontaneous abortion was reduced after adjustment for progesterone suggesting that progesterone mediates the relationship between low levels of coagulation factors and spontaneous abortion. Progesterone seems to be the primary marker for a spontaneous abortion among women seeking emergent care.