THE EFFECT OF INDUCED-ABORTION ON SUBSEQUENT FERTILITY

Objective To investigate the effect of induced abortion on subsequent fertility. Design 1. Prospective cohort study of women who had an unpl anned pregnancy at recruitment. 2. Retrospective study of women who ha d a planned pregnancy at recruitment. Setting Joint Royal College of G eneral Practitioners/Royal College of Obstetricians and Gynaecologists study based in general practice in England, Scotland and Wales, betwe en 1976 and 1987. Subjects 1. Prospective study: Four hundred and thir ty-three women with a recruitment unplanned pregnancy ending in induce d abortion (abortion group) and 1035 women with a recruitment unplanne d pregnancy which ended naturally (nonabortion group). All subsequentl y had a planned pregnancy, or were known to be trying to conceive at s ome point during the follow-up 2. Retrospective study: Nine thousand t wo hundred and ninety-nine women who presented at recruitment with a p lanned pregnancy. Main outcome measure The women's estimated length of planning time, expressed as a fertility rate ratio. Results Induced a bortion was not related to future fertility. In the prospective study, the fertility rate ratio (FRR) of the abortion group relative to the nonabortion group was 0.94 (95 % CI 0.83 to 1.07, P = 0.37). This resu lt was supported by the retrospective study, which again showed no imp ortant difference between the two groups. Conclusion Induced abortion does not appear to have an important effect on future fertility.