What potential risk does warfarin pose during pregnancy?

Warfarin, an anticoagulant, poses significant risks during pregnancy, particularly due to its ability to cross the placenta and affect the developing fetus. One of the notable risks is the increased risk of hemorrhage. During pregnancy, the altered hemostatic balance can lead to increased susceptibility to bleeding, which is exacerbated by the anticoagulant effects of warfarin. This is especially critical in the peripartum period when there are concerns about potential bleeding during delivery and postpartum.

Additionally, the use of warfarin during pregnancy is associated with potential adverse effects on the fetus, but among the options provided, the increased risk of hemorrhage directly relates to both maternal and fetal safety during the pregnancy and delivery process. The other risks mentioned have relevance but do not capture the immediate, acute concern associated with warfarin use, making the increased risk of hemorrhage the most pertinent answer in this context.