Anticoagulants to prevent recurrent placenta-mediated pregnancy complications: Is it time to put the needles away?

Placenta-mediated pregnancy complications, such as pre-eclampsia, placental abruption, birth of a small-for-gestational age infant and late pregnancy loss, are common and carry significant morbidity and mortality. The etiology of placenta-mediated pregnancy complications is likely multifactorial and may include abnormal coagulation activation of the maternal-fetal interface. The use of antepartum low-molecular-weight heparin (LMWH) prophylaxis to prevent recurrent placenta-mediated pregnancy complications has become common practice despite limited and conflicting evidence to support its use. This paper reviews the evidence, including recently published data from an individual patient level meta-analysis, which challenges the role of LMWH in preventing recurrent placenta-mediated pregnancy complications. Incorporating this recent evidence, we recommend against the use of LMWH to prevent recurrent placenta-mediated pregnancy complications in women with and without inherited thrombophilia.