Safety of Low-Molecular-Weight Heparin in Pregnancy: A Systematic Review

Abstract

SummaryUnfractionated heparin (UFH) remains the anticoagulant of choice during pregnancy. Low-molecular-weight heparins (LMWH) are an attractive alternative to UFH due to their logistic advantages and their association with a lower incidence of osteoporosis and HIT. We reviewed all published clinical reports concerning the use of LMWH during pregnancy. In addition, participants of an international interest group contributed a cohort of pregnant women treated with LMWH. Pregnancies were divided into two groups; those with and those without maternal comorbid conditions. The number of adverse fetal outcomes and the occurrence of maternal complications were evaluated in the two groups. In the group of women with comorbid conditions (n = 290), 13.4% of the pregnancies were associated with an adverse fetal outcome. In contrast, in the group of women without comorbid conditions (n = 196), 3.1% were associated with an adverse outcome, which is comparable to that seen in the normal population. We conclude that LMWH appear to be a safe alternative to unfractionated heparin as an anticoagulant during pregnancy.

Management of the obstetric antiphospholipid syndrome

“…Low molecular weight heparin has the advantage over unfractionated heparin of a longer plasma half-life and a more predictable dose response and therefore the potential for once daily administration. Furthermore, low molecular weight heparin causes less heparininduced thrombocytopenia and heparin-induced osteoporosis (62,64). Given these advantages, we prefer low molecular weight heparin, although this approach is more expensive.…”

Safety and Efficacy of Low Molecular Weight Heparin Therapy During Pregnancy: Three Year Experience at a Tertiary Care Center

“…Dolitzky et al [2] reported high efficacy and few complications of enoxaparin in patients with recurrent pregnancy loss. Sanson et al [3] reported low molecular weight heparins as an attractive alternative to unfractionated heparin due to their logistic advantages and their association with a lower incidence of osteoporosis and thrombocytopenia.…”

“…Low molecular weight heparin therapy has widespread use during pregnancy for various indications. Concerns about its safety in pregnancy have been raised and there are various studies to support its safety on maternal and fetal outcome [1][2][3]. There are no such studies from the Indian population; hence, we tried to evaluate safety and efficacy of low molecular weight heparin given during pregnancy for various indications over a period of 3 years in our hospital.…”

The use of LMWH in pregnancies at risk: new evidence or perception?

“…Most of these studies are of low quality because of their historic controls. Although LMWH is widely used in pregnancy for prophylaxis of venous thromboembolism and although relevant adverse reactions are rare [12], its application in women with fetal loss requires thorough information on the risk-benefit ratio.There is much discussion on the impact of thrombophilic factors as risk determinants of pregnancy complications including recurrent pregnancy loss or pre-eclampsia [10]. In contrast to venous thromboembolism, the data are more conflicting, particularly in women with early fetal loss.…”

“…Most of these studies are of low quality because of their historic controls. Although LMWH is widely used in pregnancy for prophylaxis of venous thromboembolism and although relevant adverse reactions are rare [12], its application in women with fetal loss requires thorough information on the risk-benefit ratio.…”