Fetal Genotype for Specific Inherited Thrombophilias Is Not Associated With Severe Preeclampsia

Abstract

Little is known about the association between fetal thrombophilias and severe preeclampsia. The objective of this study was to examine the association between fetal genotype for factor V Leiden, prothrombin, and methylene tetrahydrofolate reductase (MTHFR) mutations and severe preeclampsia. Patients with severe preeclampsia or HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome admitted to Georgetown University Hospital were retrospectively identified. Controls were patients with uncomplicated, term deliveries. Fetal DNA was extracted from placental specimens and amplified by polymerase chain reaction (PCR) with locus-specific primers. The presence of polymorphisms was determined by enzymatic digestion with specific enzymes, and analyzed by polyacrylamide gels. Statistical analysis used Student t test for continuous variables and Fisher exact test for categorical data. Patients with preeclampsia (n = 27) and controls (n = 17) were similar for maternal age, but, as expected, they were significantly different for gestational age at delivery, birth weight, Apgar scores at 5 minutes, rate of preterm delivery less than 37 weeks, and fetal growth restriction (all P <.05). DNA extraction was successful in 25 of 27 cases from the severe preeclampsia group and 14 of 17 controls. None of the placentas analyzed in the preeclamptic or control group revealed mutations in the factor V Leiden or prothrombin genes. There was no significant difference in the rate of fetuses heterozygous for MTHFR in the preeclampsia versus control group (48% vs 43%, P >.05). In our study, fetal genotype for specific inherited thrombophilias does not appear to be associated with severe preeclampsia.