beta-Subunit of human chorionic gonadotropin, ultrasound, and ectopic pregnancy: a prospective study.

This prospective study shows that the beta-subunit of human chorionic gonadotropin (beta-hCG) "screen" and ultrasound provide for nearly 100% clinical accuracy in diagnosing ectopic pregnancy in suspected cases. During the 14 months from February, 1981, to April, 1982, 81 consecutive patients believed to have ectopic pregnancies were screened. Fifty-six had a negative beta-hCG screen, thus ruling out early pregnancy complications. No false negative results were found. Twenty-seven patients had a positive screen, and 16 of these had an ectopic pregnancy. Twenty of the 27 patients with a positive beta-hCG screen underwent pelvic ultrasound examination. All of those with a positive beta-hCG screen and no intrauterine pregnancy on ultrasound had ectopic pregnancies. With the use of these clinical aids, morbidity and tubal damage are reduced because delay in operating upon those with ectopic pregnancy is avoided. Unnecessary operation is avoided in those patients who do not have an ectopic pregnancy.