Impact of inherited thrombophilias on first and second trimester maternal serum markers for aneuploidy.

OBJECTIVE

To evaluate first and second-trimester maternal serum markers in pregnancies complicated with inherited thrombophilias.

METHODS

A case-control study was conducted in 50 pregnancies complicated with hereditary thrombophilia and 100 control pregnancies.

RESULTS

Each woman with inherited thrombophilia received low molecular weight heparin (LMWH) throughout her pregnancy. Gravidity, parity, number of first-trimester and second-trimester abortions, and rate of adverse pregnancy outcomes (APO) were significantly higher in the thrombophilia group compared to the control group (P < 0.001 for all). Among the thrombophilia group median values of pregnancy associated placental protein-A (PAPP-A) (0.6 vs. 0.9; P < 0.001) and free β-human chorionic gonadotropin (β-hCG) (0.9 vs. 1.1; P = 0.001) in the first trimester; median values of α-fetoprotein (AFP) (0.7 vs. 1.1; P = 0.027), unconjugated estriol 3 (uE3) (0.9 vs. 1.1; P < 0.001), and hCG (0.7 vs. 1.2; P < 0.001) in the second trimester were significantly lower with respect to control pregnancies. Multivariate analysis revealed that low uE3 and hCG levels were independently associated with APO.

CONCLUSION

Pregnant women with hereditary thrombophilias, all of whom were treated with LMWH, had decreased levels of all first and second trimester serum markers. In addition, levels of hCG and uE3 in the second trimester could independently predict placenta-related disorders and adverse outcomes in these patients.