title: Low-molecular-weight heparins for thromboprophylaxis and treatment of venous thromboembolism in pregnancy: a systematic review of safety and efficacy.
abstract: To assess the safety and efficacy of low-molecular-weight heparins (LMWHs) for thromboprophylaxis and treatment of venous thromboembolism (VTE) in pregnancy, a systematic review of studies to the end of 2003 was undertaken. Data on VTE recurrence and side effects were extracted and cumulative incidences of VTE and adverse effects calculated. Of 81 reports identified, 64 reporting 2777 pregnancies were included. In 15 studies (174 patients) the indication for LMWH was treatment of acute VTE, and in 61 studies (2603 pregnancies) it was thromboprophylaxis or adverse pregnancy outcome. There were no maternal deaths. VTE and arterial thrombosis (associated with anti-phospholipid syndrome) were reported in 0.86% (95% confidence interval [CI], 0.55%-1.28%) and 0.50% (95% CI, 0.28%-0.84%) of pregnancies, respectively. Significant bleeding, generally associated with primary obstetric causes, occurred in 1.98% (95% CI, 1.50%-2.57%), allergic skin reactions in 1.80% (95% CI, 1.34%-2.37%), heparin-induced thrombocytopenia in 0%, thrombocytopenia (unrelated to LMWH) in 0.11% (95% CI, 0.02%-0.32%), and osteoporotic fracture in 0.04% (95% CI, < 0.01%-0.20%) of pregnancies. Overall, live births were reported in 94.7% of pregnancies, including 85.4% in those receiving LMWH for recurrent pregnancy loss. LMWH is both safe and effective to prevent or treat VTE in pregnancy.
authors.affiliation: Department of Obstetrics and Gynaecology, University of Glasgow, Glasgow Royal Infirmary, 10 Alexandra Parade, Glasgow, G31 2ER, United Kingdom. i.a.greer@clinmed.gla.ac.uk
authors.forename: Ian A
authors.initials: IA
authors.lastname: Greer
authors.forename: Catherine
authors.initials: C
authors.lastname: Nelson-Piercy
mesh_terms: D000026:Abortion, Habitual / Q000188:drug therapy / Q000517:prevention & control; D000925:Anticoagulants / Q000627:therapeutic use; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects / Q000627:therapeutic use*; D006801:Humans; D007231:Infant, Newborn; D011247:Pregnancy; D011249:Pregnancy Complications, Cardiovascular / Q000188:drug therapy* / Q000517:prevention & control; D011256:Pregnancy Outcome; D012008:Recurrence; D012449:Safety; D013923:Thromboembolism / Q000150:complications* / Q000188:drug therapy* / Q000517:prevention & control
chemical_list: D000925:Anticoagulants; D005343:Fibrinolytic Agents; D006495:Heparin, Low-Molecular-Weight