D&C and preterm birth: Is there a connection?

Results of a meta-analysis presented at the annual conference of the European Society for Human Reproduction and Embryology (ESHR) suggest that dilatation and curettage (D&C) may be a risk factor for preterm birth. The findings, by Dutch investigators, point to a need to minimize D&C and use noninvasive methods of uterine evacuation when possible.

Included in the report were 21 studies reflecting data on 1.8 million women, dating from the inception of OVID MEDLINE and OVID EMBASE to May 2014. No randomized controlled comparisons were found of women with and without a history of D&C and subsequent preterm birth. The authors noted that findings from some but not all of the cohort or case control studies reviewed were corrected for confounding factors.

Nevertheless, the meta-analysis revealed odds ratios (OR) of 1.29 (95% CI 1.17; 1.42) for preterm birth, 1.69 (95% CI 1.20; 2.38) for very preterm (<37 weeks), and 1.68 (95% CI 1.47; 1.92) for <28 weeks in women with a history of D&C. The risk of preterm birth remained higher for D&C even when the control group was limited to women with a medically managed miscarriage or induced abortion (OR 1.19; 95% CI 1.10; 1.28). For women with a history of multiple D&Cs, the OR for preterm birth (<37 weeks) was 1.74 (95% CI 1.10; 2.76). Limiting the analysis to spontaneous preterm birth subsequent to D&C, the OR was 1.44 (95% CI 1.22; 1.69).

“These data,” the authors said, “warrant caution in the use of D&C for miscarriage and induced abortions. This conclusion should contribute to the implementation of misoprostol as a noninvasive treatment option for both miscarriage and induced abortion.”