Continued pregnancy after failed first trimester abortion.

Forty-six patients with unintentional continued pregnancy were detected among a series of 65,045 first trimester abortions. Patients at greatest risk are those with very early pregnancy and those with marked uterine anteversion or retroversion or with uterine anomaly. Attention to gestational duration and uterine size as related to the amount and character of the evacuated tissue, particularly stressing identification of villi and fetal tissues, may help avoid this problem.