Age, parity, history of abortion and contraceptive choices affect the risk of repeat abortion

Abstract

Background: The rate of repeat induced abortion varies from 30% to 38% in northern Europe. Thus, repeat abortion is an important public health issue. However, risk factors as regards repeat abortion are poorly understood. We characterized risk factors related to sociodemographic characteristics, history of abortion and post-abortal contraception.

Study design: A prospective cohort study of 1269 women undergoing medical abortion between August 2000 and December 2002 was conducted. The subjects were followed via the Finnish Registry of Induced Abortions until December 2005, the follow-up time (mean+/-SD) being 49.2+/-8.0 months.

Results: Altogether, 179 (14.1%) of the subjects requested repeat abortion within the follow-up time. In univariate analysis, a history of prior abortion, being parous, young age, smoking and failure to attend the follow-up visit were associated with repeat abortion. Immediate--in contrast to postponed--initiation of any contraceptive method was linked to a lower risk of repeat abortion. In comparison with combined oral contraceptives, use of intrauterine contraception was most efficacious in reducing the risk of another pregnancy termination. In multivariate analysis, the effects of young age, being parous, smoking, a history of prior abortion and type of contraception on the risk of another abortion persisted.

Conclusions: An increased focus on young women, parous women and those with a history of abortion may be efficacious in decreasing repeat abortion. Contraceptive choices made at the time of abortion have an important effect on the rate of repeat abortion. Use of intrauterine contraceptives for post-abortal contraception was associated with decreased risk of repeat abortion.