Low beta-hCG is associated with poor prognosis in association with an embryo with positive cardiac activity.

Seven pregnancies with positive fetal heart activity and low or very low serum beta-human chorionic gonadotropin (beta-hCG) levels were investigated. The gestational age by dates was between 6 weeks 3 days and 8 weeks 4 days at the time of the first ultrasound scan and beta-hCG ranged between 282 and 10,000 mIU/ml of the Second International Standard. The crown-rump lengths ranged between 6 and 13 mm and heart activity was always detected.