Early pregnancy failure: factors affecting successful medical treatment.

BACKGROUND: The results of medical treatment for early pregnancy failure are conflicting.

OBJECTIVES: To determine whether gestational sac volume measurement as well as other variables can predict the success rate of medical treatment for early pregnancy failure.

METHODS: The study group comprised 81 women diagnosed with missed abortion or anembryonic pregnancy who consented to medical treatment. Demographic data were collected and beta-human chorionic gonadotropin level was documented. Crown-rump length and the sac volume were measured using transvaginal ultrasound. TVU was performed 12-24 hours after intravaginal administration of 800 micro g misoprostol. If the thickness of the uterine cavity was less than 30 mm, the women were discharged. If the sac was still intact or the thickness of the uterine cavity exceeded 30 mm, they were offered an additional dosage of intravaginal misoprostol or surgical uterine evacuation.

RESULTS: Medical treatment successfully terminated 32 pregnancies (39.5%), 30 after one dose of misoprostol and 2 after two doses (group A); 49 underwent surgical evacuation (group B), 47 following one dose of misoprostol and 2 following two doses. There were no significant differences between the groups in age and gestational week. Gestational sac volume did not differ between groups A and B (10.03 and 11.98 ml respectively, P = 0.283). Parity (0.87 and 1.43, P = 0.015), previous pregnancies (2.38 and 2.88, P = 0.037), and betahCG concentration (6961 and 28,748 mlU, P = 0.013) differed significantly between the groups.

CONCLUSIONS: Gestational sac volume is not a predictor of successful medical treatment for early pregnancy failure. Previous pregnancies and deliveries and higher betahCG concentration negatively affect the success rate of medical treatment.