The authors noted that UFH may also be administered during pregnancy and has a comparable safety profile to LMWH but requires activated partial thromboplastin time (aPTT) monitoring and is associated with a higher risk of HIT. One potential advantage of UFH is when rapid reversal of anticoagulant effect is needed; however, a twice-daily LMWH regimen may also be used in these patients, and in cases where rapid reversal is required, protamine sulfate may be administered. Vitamin K antagonists (VKA) are contraindicated in pregnancy because of teratogenic effects, but they can be safely administered during breastfeeding.

Direct oral anticoagulants (DOACs) are contraindicated during pregnancy and breastfeeding, but they are a suitable alternative in the postpartum setting, if women do not breastfeed and long-term use is intended. If a patient does become pregnant while receiving a DOAC, the authors recommended switching to LMWH immediately.

“In postpartum nonbreastfeeding patients, I do not have a preference for a specific DOAC,” commented Dr Middeldorp in an email interview.

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“Management of delivery, including the type of analgesia, requires a multidisciplinary approach and depends on local preferences and patient-specific conditions,” the authors wrote in their review. “Several options are possible and include waiting for spontaneous delivery with temporary interruption of LMWH.”

The risk of recurrent VTE in subsequent pregnancies is 6% to 10% without prophylaxis.6-8 As a result, prophylactic anticoagulant therapy is recommended in most women with a history of VTE.

To read the comprehensive list of recommendations containing qualifying remarks, readers should refer to the full publication in Blood.

Disclosure: Some guideline authors have declared affiliations with or received funding from the pharmaceutical industry. Please refer to the original study for a full list of disclosures.


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