TABLE 28.

Anticoagulation Strategies During Pregnancy.

Antenatal Options
	Method 1	Method 2	Method 3	Alternative Method 4
First trimester	Warfarin ≤5 mg	LMWH	UFH	LMWH
Second trimester	Warfarin	Warfarin	Warfarin	LMWH
Third trimester	Warfarin	Warfarin	Warfarin	LMWH
Delivery Planning
	Method 1		Method 2
1 wk before	Discontinue warfarin → continuous IV UFH		Dose-adjusted LMWH
36 h before	Continuous IV UFH		Switch to continuous IV UFH
4-6 h before	Stop IV heparin		Stop IV heparin

Adapted with permission from Otto et al.¹⁵ Copyright 2021 American Heart Association, Inc., and American College of Cardiology Foundation.

IV indicates intravenous; LMWH, low-molecular-weight heparin; and UFH, unfractionated heparin.