Objective: To investigate the following: 1) the influence of pelvic inflammatory disease, postabortal complications, previous induced abortions, and age on the rate of subsequent spontaneous abortion; and 2) the influence of pelvic inflammatory disease, postabortal complications, previous induced abortions, previous spontaneous abortions, age, and parity on the rates of dyspareunia, dysmenorrhea, and chronic pelvic pain.
Methods: The study population consisted of a cohort of 1229 pregnant women, of whom 868 were referred for delivery and 361 for first-trimester abortion. Outcome measures examined were spontaneous abortion and the occurrence of dyspareunia, dysmenorrhea, and chronic pelvic pain.
Results: In 839 women without previous induced abortion, a history of pelvic inflammatory disease was associated with an increased risk of spontaneous abortion (odds ratio 1.55, 95% confidence interval [CI] 1.03-2.33); women above age 33 had a lower risk of spontaneous abortion (odds ratio 0.53, 95% CI 0.30-0.96). In 382 women with previous induced abortion, the influence of age on the rate of spontaneous abortion was continuous so that an increase of 1 year of age reduced the risk of spontaneous abortion by 0.91 (95% CI 0.85-0.96). Women with any previous pelvic inflammatory disease, when compared with those without, more often had dyspareunia (14 versus 3%; odds ratio 3.87, 95% CI 2.35-6.37) and chronic pelvic pain (6 versus 0.4%; odds ratio 13.07, 95% CI 10.09-16.04). Age was inversely associated with the incidence of dysmenorrhea (odds ratio 0.94, 95% CI 0.91-0.97).
Conclusion: Pelvic inflammatory disease is associated with later spontaneous abortion, whereas age correlates inversely with the rate of spontaneous abortion. Spontaneous and postabortal pelvic inflammatory diseases carry significantly elevated risks of dyspareunia and chronic pelvic pain.