Objective: The purpose of this study was to investigate associations between fetal inherited thrombophilia and adverse pregnancy outcomes, including pregnancy-induced hypertensive disorders (PIHD), antepartum hemorrhage (APH), small-for-gestational age <10th percentile (SGA), and preterm birth (PTB).
Study design: Seven hundred and seventeen cases and 609 controls were genotyped for Factor V Leiden (FVL, G1691A), Prothrombin gene mutation (PGM, G20210A), and Methylenetetrahydrofolate reductase (MTHFR) C677T and MTHFR A1298C using DNA from newborn screening cards.
Results: For babies born <28 weeks' gestation, PGM was associated with an increased risk of SGA (OR 6.40, 95%CI 1.66-24.71) and APH with SGA (OR 6.35, 95%CI 1.63-24.75). Homozygous MTHFR A1298C was associated with an increased risk of SGA for babies born 28-31 weeks gestation (OR 4.00, 95%CI 1.04-15.37), and with APH and SGA for babies born <32 weeks' gestation (OR 3.57, 95%CI 1.09-11.66). Homozygous MTHFR C677T was associated with a reduced risk of PTB and SGA (OR 0.52, 95%CI 0.28-0.96) for babies born 32 to 36 weeks' gestation. Homozygous FVL decreased the risk of PTB <32 weeks' gestation (OR 0.55, 95%CI 0.31-0.98).
Conclusion: Fetal thrombophilic polymorphisms may be related to adverse pregnancy outcomes, in particular SGA.