OC018: Should complete miscarriages be followed up with serum human chorionic gonadotrophin levels?

Abstract

Background: Ultrasonography is highly reliable in the management of women with early pregnancy complications. An endometrial cut-off < 15 mm with no retained products of conception has been used to classify complete miscarriage (CM) on transvaginal sonography (TVS). However despite a history of heavy vaginal bleeding, a proportion of these women have an undiagnosed ectopic pregnancy (EP). We evaluated the need for hormonal follow up in women with a history and scan findings suggestive of CM. Materials and methods: Prospective observational study. 5918 consecutive women presented to the Early Pregnancy Unit −223 (3.8%) were classified CM on the basis of a history of heavy vaginal bleeding and the above sonographic criteria. 56 were not pregnant and 24 were lost to follow up. 143 were included in the analysis. Serum human chorionic gonadotrophin (hCG) levels were taken at presentation and 48 hours later. All women were followed up until hCG < 5 U/L or a cyesis was visualised on TVS. Results: 131/143 (91.6%) CM confirmed according to hCG follow up. 8/143 (5.6%) confirmed to be EP requiring further treatment. 2/143 (1.4%) persisting pregnancies of unknown location (PUL) requiring methotrexate therapy. 2/143 (1.4%) intrauterine pregnancies – one blighted ovum and one ongoing IUP. If hCG levels rose, 10/12 (83%) required intervention. Conclusions: Diagnosis of complete miscarriage based on history and scan findings alone is unreliable, as up to 6% will have an ectopic pregnancy. If hCG levels do not fall, these women should be followed closely until the location of the pregnancy is confirmed.