Antepartum bleeding of unknown origin in the second half of pregnancy: a review.

Unlabelled: The objective of this study was to determine the prevalence, adverse pregnancy complications, and optimal management of pregnancies complicated by bleeding in the second half of pregnancy of an unknown origin (ABUO). A MEDLINE search from 1966 through November 2004 using the search terms "antepartum hemorrhage" or "hemorrhage" or "uterine hemorrhage" and "pregnancy complications" and "cardiovascular complications" and "second trimester pregnancy" or "third trimester pregnancy" was undertaken. The inclusion criteria focused on bleeding not resulting from placenta previa or abruption or to any known cause.