Venous thromboembolism during pregnancy: a retrospective study of enoxaparin safety in 624 pregnancies

Objective To assess the maternal, fetal and neonatal safety of enoxaparin i n pregnant women Alto require antithrombotic therapy. Design Retrospective analysis of case note,,, of women who received enoxapa rin during pregnancy, Irrespective of close, duration and reason for treatm ent. Setting Fifty-five French perinatal centres. Sample Data from 624 pregnancies in 604 women between 1988 and 1997. The in cidence of previous thromboembolism was 29.8%, known thrombophilia 15.2%. Methods Indication. regimen of enoxaparin and outcome measures were reporte d for each pregnancy. Information was obtained from case records. validated by research staff and analysed hv an independent scientific committee, Main outcome measures Incidence. seriousness and causality of maternal, fet al and neonatal adverse events, pregnancy outcome. and incidence of venous thromboembolism. Results Enoxaparin was administered for treatment of an acute episode in 49 cases and for thromboprophylaxis in 574 cases. Serious maternal haemorrhag e Occurred in 11 cases during pregnancy (1.8%), one being reasonably relate d to enoxaparin. and in nine cases at delivers (1.4%) all unrelated to enox aparin. Maternal thrombocytopenia was reported in 10 cases (1.6%) mo being serious but unrelated to enoxaparin. Eight pregnancies ended in stillbirth (1.1%). Among the 693 lice birth,,. 17 major congenital abnormalities (2.5% ) and 10 serious neonatal haemorrhages ( 1.4%) were reported. None of the f etal Or neonatal adverse events was related to enoxaparin. Eight venous thr omboembolic events (1.3%) were reported. Conclusions The incidence of adverse events reported could he explained by the high risk profile of the study population. Overall, this retrospective study suggests enoxaparin is well tolerated during pregnancy.