Inherited thrombophilias are not yet established as a cause of placenta-mediated pregnancy complications, such as fetal growth restriction, preeclampsia, abruption, and pregnancy loss. An inherited thrombophilia is only one of many factors that lead to development of these diseases and is unlikely to be the unique factor that should drive management in subsequent pregnancies. The paucity of evidence for benefit, coupled with a small potential for harm, suggests that low molecular weight heparin should be considered an experimental drug for these indications until data from controlled trials are published. At present, women with a history of placenta-mediated pregnancy complications, with or without a thrombophilia, should be followed closely without routine prophylactic low molecular weight heparin other than for prevention of venous thromboembolism in limited circumstances.
Inherited thrombophilias are not yet established as a cause of placenta-mediated pregnancy complications.
From the 1Thrombosis Program, Division of Hematology, Department of Medicine, University of Ottawa, and 2Clinical Epidemiology Unit, Ottawa Health Research Institute, the Ottawa Hospital, Ottawa, Ottawa, Ontario, Canada; 3Department of Obstetrics and Gynecology, Yale University, New Haven, Connecticut; 4Department of Obstetrics and Gynecology, University of Auckland, Auckland, New Zealand; 5Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands; 6Department of Medicine, McGill University, Montreal, Quebec, Canada; 7Department of Medicine, IRCCS Maggiore Hospital Foundation, Milan, Italy; 8Department of Obstetrics and Gynecology, University of Adelaide, Adelaide, Australia; 9Department of Medicine, Brown University, Providence, Rhode Island; and 10Hull York Medical School, York, United Kingdom.
Corresponding author: Dr. M. Rodger, Division of Hematology, the Ottawa Hospital, General Campus, 501 Smyth Road, Box 201, Ottawa, Ontario, Canada K1H 8L6; e-mail: firstname.lastname@example.org.
Financial Disclosure Dr. McLintock has received honoraria and financial support to attend international conferences From Sanofi-Aventis (Bridgewater, NJ). Dr. Kahn has received honoraria From Sanofi-Aventis, Pfizer (New York, NY), and Leo Pharma (Copenhagen, Denmark). Dr. Rodger has received grant funding From Pfizer, Sanofi-Aventis, Boehringer Ingelheim (Ingelheim, Germany), Bayer (Leverkusen, Germany), GTC Therapeutics (Boston, MA), Biomerieux (Marcy l'Etoile, France), and Leo Pharma. Dr. Rodger has served on an advisory board for Boehringer Ingelheim, but was not paid. The other authors have no potential conflicts of interest to disclose.