Subchorionic Hemorrhage in the Second and Third Trimesters of Pregnancy: A Review

Importance: Subchorionic hemorrhage (SCH) in the second and third trimesters of pregnancy can be associated with maternal morbidity and fetal morbidity/mortality. Management of SCH in the second or third trimesters can be complicated, especially in the setting of a large SCH that requires hospitalization and blood transfusion. Objective: The aim of this review is to describe SCH in second and third trimesters, risk factors, diagnosis, maternal and fetal outcomes, and management of this uncommon pregnancy complication. Evidence Acquisition: A PubMed, Web of Science, and CINAHL search was undertaken with no limitations on the number of years searched. Results: There were 123 abstracts and/or articles reviewed, with 48 articles being the basis of review. The only known risk factors for SCH are maternal factor deficiency and anticoagulation therapy. The diagnosis is usually made by ultrasound imaging. Subchorionic hemorrhage in second and third trimesters has been associated with several adverse fetal outcomes including preterm birth, preterm prelabor rupture of membranes, fetal growth restriction, fetal demise, and neonatal pulmonary morbidity. There is no proven treatment for SCH, although there are several investigational therapies reported. Conclusions: Subchorionic hemorrhage can be complex and difficult to manage in the second and third trimesters. There are no recommendations or guidelines for management; however, serial growth ultrasounds, umbilical artery Doppler studies, and antenatal fetal testing should be considered particularly if the SCH is large or treatment requires a maternal blood transfusion. Relevance: Subchorionic hemorrhage in the second and third trimester is associated with poor fetal outcomes and maternal morbidity, especially if the SCH is significant.