Induced abortion as a risk factor for subsequent fetal loss.

The relation between past induced abortions and subsequent fetal loss is still unclear. We report a case-control study with 331 cases of first spontaneous abortion and 993 controls with no previous spontaneous abortion and a normal pregnancy at the same period of pregnancy. In comparison with primigravid women, the odds ratio for a fetal loss in the current one was 1.41 [95% confidence interval (CI) = 0.81-2.43] among women with one previous pregnancy ending in induced abortion, 4.43 (95% CI = 1.46-13.36) among those with two previous induced abortions out of two pregnancies, and 1.35 (95% CI = 0.64-2.82) among women with three or more previous pregnancies ending in one or more induced abortions.