Maternal surgery and anesthesia during pregnancy and risk of birth defects in the National Birth Defects Prevention Study, 1997-2011

Background: There is little recent research on the teratogenicity of maternal anesthesia exposure. We used National Birth Defects Prevention Study data to describe surgical procedures conducted during pregnancy and to estimate the risk of birth defects associated with periconceptional anesthesia exposure. Methods: We used logistic regression to assess associations between general and local anesthesia for surgery during the periconceptional period and specific birth defects. We calculated odds ratios and 95% confidence intervals for 25 birth defects with at least five exposed cases (11,501 controls, 24,337 cases), adjusted for maternal race/ethnicity, age, body mass index, periconceptional exposure to X-ray, CT, or radionuclide scans, and study site. Results: The most commonly reported procedures were dental, dermatologic, and cervical cerclage procedures, regardless of gestational timing. Overall, 226 case and 73 control women reported periconceptional general anesthesia; 230 case and 89 control women reported periconceptional local anesthesia. Women who reported general or local anesthesia were disproportionately non-Hispanic white and were more likely to report periconceptional opioid use and at least one periconceptional X-ray/CT/radionuclide scan. Women who reported general anesthesia were also more likely to report periconceptional injury. We did not observe any significant associations between either type of anesthesia exposure and the birth defects studied. Odds ratios were generally close to null and imprecise. Conclusions: Our study population reported a wide range of surgical procedures during pregnancy, requiring both general and local anesthesia. Our findings suggest that periconceptional anesthesia is not strongly associated with the birth defects assessed in this study.