Pregnancy failure and heritable thrombophilia.

Heritable thrombophilia is associated with an increased risk for pregnancy failure, defined as sporadic and recurrent miscarriage, late fetal loss, and other vascular pregnancy complications such as preeclampsia and intrauterine growth retardation. The pathogenesis is likely to include effects on trophoblast differentiation and not solely hypercoagulability. This is in line with the observation that most recurrent miscarriages occur early. Therapeutic options include aspirin as well as low-molecular-weight heparin. However, in women with heritable thrombophilia and unexplained recurrent pregnancy loss, evidence is not available as published trials have not used an adequate comparator (no treatment or placebo). Currently, randomized controlled trials with no treatment or placebo are being carried out and results should be awaited before implementing a potentially harmful intervention in pregnant women with heritable thrombophilia and a history of pregnancy failure. Both infertility and pregnancy failure are extremely distressing for couples with the desire to have children. Pregnancy failure comprises (recurrent) early miscarriage, as well as late pregnancy loss. The role of heritable thrombophilia in pregnancy failure is reviewed, with a focus on recurrent miscarriage, in terms of epidemiology, etiology, and potential therapeutic implications.