Exposure to cox-2 inhibitors (coxibs) during the first trimester and pregnancy outcome: a prospective observational cohort study

Purpose Cox-2-inhibitors (coxibs) are not recommended in pregnancy but early exposure may occur, for instance in unplanned pregnancies. Experience in pregnancy is limited leading to concerns in patients and their health care providers. Therefore, further data on coxibs and their effects on embryogenesis are needed. Methods This observational cohort study evaluates pregnancies ascertained in Germany during the study period from January 2000 to January 2016. A cohort of 174 women exposed to coxibs in the first trimester was compared to a randomly selected cohort of 521 women without exposure to coxibs, other nonsteroidal anti-inflammatory drugs or known teratogens. Results The overall rate of major birth defects was not significantly increased in the study cohort (2.9 vs. 2.7%, OR 1.08, 95% CI 0.34–3.42; OR adjusted 0.96, 95% CI 0.28–3.26). The cumulative incidence of spontaneous abortions was nonsignificantly lower in the exposed cohort (14.3 vs. 20.0%; HR, 0.90, 95% CI 0.51–1.58; HR adjusted, 0.87; 95% CI, 0.49–1.56). Elective terminations of pregnancies (ETOP), mainly for ‘social’ reasons, were more frequent in the coxib cohort (17.5 vs. 7.0%, HR, 2.31; 95% CI, 1.26–4.24; HR adjusted 2.12, 95% CI 1.13–3.97). Conclusions Our study results support the assumption that coxibs are not major teratogens. Considering the still limited evidence basis on coxib exposure during pregnancy, well-established alternatives should be preferred.