The safety of low molecular weight heparin therapy during labor.

Objective: Current recommendations are to discontinue low molecular weight heparin (LMWH) at least 24 hours prior to labor induction or administering epidural anesthesia. We assessed the safety of discontinuing LMWH 12-24 hours before delivery.

Methods: We evaluated the prevalence of hemorrhagic complications during labor, cesarean or epidural catheter placement in 284 women treated with enoxaparin during pregnancy as compared with 16132 untreated women. Treated participants were divided into subgroups by the various intervals between last LMWH dose hemorrhage-prone events (vaginal delivery,epidural, cesarean etc.). The rate of hemorrhagic complications and hemoglobin values were compared between the study and control groups.

Results: Postpartum hemorrhage was uncommon and occurred in 2.1% and 1.9% in study and control groups, respectively (p=0.13). Antenatal as well as postnatal hemoglobin values were very similar for treated and untreated women. No differences were noted between women who discontinued enoxaprin 12-24 hours before labor and those who discontinued treatment later with regard to maternal hemorrhagic complications. No spinal hematomas were report among 12792 treated and un-treated women who had epidural or spinal block. No hemorrhagic neonatal complications were encountered.

Conclusion: Discontinuing LMWH more than 12 hours before delivery is safe in relation to maternal hemorrhagic complications.