Risks Associated With Anticoagulant Use in Pregnancy
A daily dose of warfarin had no significant affect on fetal risks.
HealthDay News — Anticoagulation for mechanical heart valves during pregnancy is associated with distinct maternal and fetal risks, according to a review published in the Journal of the American College of Cardiology.
Zachary L. Steinberg, MD, from the University of Washington School of Medicine in Seattle, and colleagues compared the risk of adverse maternal and fetal outcomes in pregnant women with mechanical heart valves receiving different methods of anticoagulation. Data were included for 800 pregnancies from 18 publications. The women were receiving either a vitamin K antagonist (VKA) throughout pregnancy; low-molecular weight heparin (LMWH) throughout pregnancy; LMWH for the first trimester followed by a VKA; or unfractionated heparin (UHA) for the first trimester followed by a VKA.
The researchers found that the composite maternal risk was lowest with VKA compared with LMWH, LMWH and VKA, or UFH and VKA (5% vs 16%, 16%, and 16% percent, respectively). The lowest composite fetal risk was seen with LMWH vs VKA, LMWH and VKA, or UFH and VKA (13% vs 39%, 23%, and 34%, respectively). Women taking ≤5 mg daily warfarin and those with an LMWH regimen had no significant difference in fetal risk.
"VKA treatment was associated with the lowest risk of adverse maternal outcomes, whereas the use of LMWH throughout pregnancy was associated with the lowest risk of adverse fetal outcomes," the authors write.
One author disclosed financial ties to GlaxoSmithKline.
- Steinberg ZL, Dominguez-Islas CP, Otto CM, Stout KK, Krieger EV. Maternal and fetal outcomes of anticoagulation in pregnant women with mechanical heart valves. J Am Coll Cardiol. 2017;69(22):2681-2691. doi:10.1016/j.jacc.2017.03.605
- Elkayam U. Anticoagulation therapy for pregnant women with mechanical prosthetic heart valves. J Am Coll Cardiol. 2017;69(22). doi:10.1016/j..jacc.2017.04.034