Is thrombophilia associated with placenta-mediated pregnancy complications? A prospective cohort study.

BACKGROUND: Case control studies suggest that genetic thrombophilias increase the risk of placenta-mediated pregnancy complications (pregnancy loss, small for gestational age (SGA), preeclampsia and/or placental abruption). Cohort studies have not supported this association but were underpowered to detect small effects. OBJECTIVE: To determine if factor V Leiden (FVL) or the prothrombin gene mutation (PGM) were associated with placenta-mediated pregnancy complications. PATIENTS/METHODS: A prospective cohort of unselected, consenting pregnant women at three Canadian tertiary care hospitals had blood drawn in the early second trimester and were genotyped for FVL and PGM after delivery. The main outcome measure was a composite of pregnancy loss, SGA < 10th percentile, preeclampsia or placental abruption. RESULTS: Complete primary outcome and genetic data were available for 7343 women. Most were Caucasian (77.7%, n = 5707), mean age was 30.4 (± 5.1) years, and half were nulliparous. There were 507 (6.9%) women with FVL and/or PGM; 11.64% had a placenta-mediated pregnancy complication. Of the remaining 6836 women, 11.23% experienced a complication. FVL and/or PGM was associated with a relative risk of 1.04 (95% CI, 0.81-1.33) for the composite outcome, with similar results after adjustment for important covariates. CONCLUSIONS: Carriers of FVL or PGM are not at significantly increased risk of these pregnancy complications.

OS040. Effect of folic acid supplementation in pregnancy on preeclampsia- Folic acid clinical trial (FACT).

INTRODUCTION: Observational studies suggest that folic acid supplementation during pregnancy can reduce the risk of preeclampsia (PE). No randomized controlled trial has been conducted to demonstrate the effect of folic acid supplementation on PE. OBJECTIVES: FACT aims to determine efficacy on a new PE prevention strategy of high dose folic acid supplementation from early pregnancy (8(0/7) to 16(6/7)weeks of gestation) until delivery in women with high risk of developing PE. DESIGN: FACT is an international, multi-centre, double-blind, placebo controlled clinical trial of 3656 women. Eligible women will be randomised in a 1:1 ratio to folic acid 4.0mg or placebo. POPULATION: Pregnant women (8(0/7)and 16(6/7) weeks of gestation) ⩾18 years of age, taking ⩽1.1mg of folic acid supplementation who fulfill at least one of the following identified risk factors for PE. Pre-existing hypertension (blood pressure ⩾90mmHg on two separate occasions or at least 4h apart prior to randomization, or use of antihypertensive medication during this pregnancy specifically for the treatment of hypertension prior to randomization), pre-pregnancy diabetes (Type I or Type II DM), twin pregnancy, history of PE in a previous pregnancy, BMI ⩾35kg/m(2) within 3 months prior this pregnancy or during the first trimester of this pregnancy. PRIMARY OUTCOME: PE is defined as blood pressure ⩾d90mmHg on two occasions ⩾4 h apart and proteinuria developed in women greater than 20 weeks of gestation. Or HELLP (Haemolysis, Elevated, Liver Enzymes, Low Platelets) syndrome Or superimposed PE, defined as history of pre-existing hypertension (diagnosed pre-pregnancy or before 20 weeks' gestation) with new proteinuria. Proteinuria is defined as: Analysis plan: Intent-to-Treat (ITT) population will be analyzed. Chi-square test will be used in the comparison of incidence of PE between the intervention and placebo groups for analysis of the primary outcome. RESULTS: The Ottawa Hospital randomized the first FACT subject in April 2011. As of February 29th, 2012, 62 subjects have been randomized. There are currently 18 Canadian sites participating in FACT, of which 10 are actively recruiting and 8 are pending site activation. Internationally, Argentina, Australia and the United Kingdom are anticipating first recruits in the late spring of 2012. Israel and Holland are expected to begin enrolment as early as the fall of 2012. CONCLUSION: Recruitment is on target and expected to end August 2014. Results from this large scale trial will provide a definitive answer to the important question whether folic acid supplementation can prevent PE.