Objective: The purpose of the present study was to examine the association between spontaneous consecutive recurrent abortions and pregnancy complications such as hypertensive disorders, abruptio placenta, intrauterine growth restriction and cesarean section (CS) in the subsequent pregnancy.
Methods: A population-based study comparing all singleton pregnancies in women with and without two or more consecutive recurrent abortions was conducted. Deliveries occurred during the years 1988-2002. Stratified analysis, using a multiple logistic regression model was performed to control for confounders.
Results: During the study period 154,294 singleton deliveries occurred, with 4.9% in patients with history of recurrent consecutive abortions. Using a multivariate analysis, with backward elimination, the following complications were significantly associated with recurrent abortions-advanced maternal age, cervical incompetence, previous CS, diabetes mellitus, hypertensive disorders, placenta previa and abruptio placenta, mal-presentations and PROM. A higher rate of CS was found among patients with previous spontaneous consecutive recurrent abortions (15.9% versus 10.9%; OR = 1.6; 95% CI, 1.5-1.7; P < 0.001). Another multivariate analysis was performed, with CS as the outcome variable, controlling for confounders such as placenta previa, abruptio placenta, diabetes mellitus, hypertensive disorders, previous CS, mal-presentations, fertility treatments and PROM. A history of recurrent abortion was found as an independent risk factor for CS (OR = 1.2; 95% CI, 1.1-1.3; P < 0.001). About 58 cases of inherited thrombophilia were found between the years 2000-2002. These cases were significantly more common in the recurrent abortion as compared to the comparison group (1.2% versus 0.1%; OR = 11.1; 95% CI, 6.5-18.9; P < 0.001).
Conclusion: A significant association exists between consecutive recurrent abortions and pregnancy complications such as placental abruption, hypertensive disorders and CS. This association persists after controlling for variables considered to coexist with recurrent abortions. Careful surveillance is required in pregnancies following recurrent abortions, for early detection of possible complications.