CHANGE IN SERUM BETA-HUMAN CHORIONIC-GONADOTROPIN AFTER ABORTION WITHMETHOTREXATE AND MISOPROSTOL

OBJECTIVE: The purpose of this study was to determine the normal beta- human chorionic gonadotropin change within 24 hours after a medical ab ortion. Because a medical abortion creates a ''miscarriage,'' these da ta can represent the serum beta-human chorionic gonadotropin changes t hat would occur with a complete spontaneous abortion. Knowledge of nor mal beta-human chorionic gonadotropin changes after a spontaneous abor tion may help to differentiate within a 24-hour period a complete from an incomplete spontaneous abortion or an ectopic pregnancy. STUDY DES IGN: Data from recent trials that used methotrexate and misoprostol fo r abortion at less than or equal to 56 days' gestation were reviewed. Patients from each of four trials were included in this analysis if (1 ) they received both methotrexate intramuscularly and misoprostol vagi nally and (2) they had serum beta-human chorionic gonadotropin levels drawn on both the day of misoprostol administration and the next day. RESULTS: The change in serum beta-human chorionic gonadotropin was eva luated in 86 patients. Subjects who had a complete abortion after rece iving methotrexate and a single dose of misoprostol had a decline in s erum beta-human chorionic gonadotropin of 66% +/- 8%. Ali other subjec ts had a decline of 25% +/- 19% (p = 0.0001). CONCLUSIONS: An aborting pregnancy, if the abortion has occurred, should have a beta-human cho rionic gonadotropin decrease of at least 48% within approximately 24 h ours. This decline, however, does not guarantee that the abortion is c omplete. A patient with a serum beta-human chorionic gonadotropin leve l that has not declined by a minimum of approximately 50% over 24 hour s is unlikely to have a complete abortion.