Advertisement

685: Prior termination of pregnancy as independent risk factor for preterm birth: a systematic review and meta-analysis

      Objective

      To evaluate the risk of preterm birth (PTB) among women with history of either induced (I-TOP) or spontaneous (S-TOP) termination of pregnancy.

      Study Design

      Electronic databases were searched from their inception until January 2015 with no limit for language. We included all studies of women with prior I-TOP or S-TOP compared to controls (women without history of TOP) which reported data about the subsequent pregnancy. The primary outcome was the incidence of PTB<37 weeks. Studies about I-TOP and S-TOP were analyzed separately. Within these categories, studies about surgical TOP and studies about medical TOP were analyzed separately.

      Results

      We included 36 studies in this meta-analysis (1,047,683 women). Thirty-one studies reported data regarding prior I-TOP, while 5 regarding prior S-TOP. Out of the 31 I-TOP studies, 28 included 913,297 women with history of surgical I-TOP, while three included 10,253 women with prior medical I-TOP. Figure and Table show the pooled results. Women with history of surgical I-TOP had a significantly higher risk of PTB (OR 1.52, 95% CI 1.08 to 2.16; Figure), low birth weight (OR 1.41, 95% CI 1.22 to 1.62) and small for gestational age (OR 1.19, 95% CI 1.01 to 1.42; Table) compared to control. Only three studies reported data about subsequent pregnancy in women with prior medical I-TOP. Women with prior medical I-TOP had a similar risk of PTB compared to those who did not have history of TOP (OR 1.50, 95% CI 1.00 to 2.25; Figure). Five studies reported data about subsequent pregnancy in women with prior spontaneous TOP. Women with prior surgical S-TOP had a higher risk of PTB compared to those who did not have history of TOP (OR 1.19, 95% CI 1.03 to 1.37). No studies were found on medical S-TOP.