The use of low-molecular-weight heparins in pregnancy--how safe are they?
OBJECTIVE
Low-molecular-weight heparins are in widespread use during pregnancy. As with every treatment in pregnant patients, concerns have been raised about the safety of Low-molecular-weight heparins. The purpose of the present article is to review recent advances, published during the past year, that have studied the maternal, fetal, and neonatal safety of Low-molecular-weight heparins in pregnant women.


RESULTS
Low-molecular-weight heparins do not increase the risk of maternal bleeding during pregnancy. Closed management is needed during the peripartum period, and discontinuing Low-molecular-weight heparins at least 12 h before delivery seems sufficient to prevent post-partum haemorrhage. The incidence of Low-molecular-weight heparins-induced immune reaction is low. Fondaparinux or danaparoid may be used as an alternative option in pregnant women with heparin-induced thrombocytopenia. Long-term Low-molecular-weight heparins therapy may be associated with osteopenia. Calcium vitamin D supplementation during pregnancy may reduce the risk of Low-molecular-weight heparins-induced osteoporosis. As Low-molecular-weight heparins do not cross the placenta, no fetal or neonatal complication has been reported. Beyond the safety question, Low-molecular-weight heparins have the potential to improve the live-birth rate in high-risk pregnancies (antiphospholipid syndrome, thrombophilia, or recurrent fetal loss).


CONCLUSIONS
Recent studies have confirmed the safety of Low-molecular-weight heparins therapy during pregnancy. The risk of potential side effects is low for both the mother and the neonate.
Deruelle
Philippe
P
Clinique d'Obstétrique. Hôpital Jeanne de Flandre, CHRU de Lille, France. p-derulle@chru-lille.fr
Coulon
Capucine
C
D000925:Anticoagulants / Q000009:adverse effects* / Q000627:therapeutic use; D050071:Bone Density Conservation Agents / Q000008:administration & dosage*; D001851:Bone Diseases, Metabolic / Q000517:prevention & control; D002136:Calcium, Dietary / Q000008:administration & dosage; D005260:Female; D006495:Heparin, Low-Molecular-Weight / Q000009:adverse effects* / Q000627:therapeutic use; D006801:Humans; D006473:Postpartum Hemorrhage / Q000517:prevention & control; D011247:Pregnancy; D011250:Pregnancy Complications, Hematologic / Q000188:drug therapy*; D011256:Pregnancy Outcome; D018570:Risk Assessment; D012449:Safety; D013921:Thrombocytopenia / Q000139:chemically induced / Q000517:prevention & control; D013927:Thrombosis / Q000517:prevention & control*; D014807:Vitamin D / Q000008:administration & dosage
D000925:Anticoagulants; D050071:Bone Density Conservation Agents; D002136:Calcium, Dietary; D006495:Heparin, Low-Molecular-Weight; D014807:Vitamin D