(B-292) Perinatal outcomes after the use of Japanese traditional medicines containing ephedra during pregnancy: the Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study

Background: Information on the safety of medication use during pregnancy is limited. The Tohoku Medical Megabank Project Birth and Three-Generation Cohort Study (TMM BirThree Cohort Study) collects such information. Japanese traditional (Kampo) medicines containing ephedra (KE) are commonly used by pregnant women in Japan. We previously reported that there was no significant association between the use of KE during the first trimester of pregnancy and major congenital malformations. However, there is a lack of data on the potential risks of other perinatal outcomes associated with the use of KE during pregnancy.

Objectives: This study evaluated the risk of adverse perinatal outcomes associated with KE use during pregnancy, using data from the TMM BirThree Cohort Study.

Methods: Questionnaires were distributed to 23,730 pregnant women participating in the TMM BirThree Cohort Study (July 2013–March 2017) at approximately 12 and 26 weeks of gestation. We constructed a propensity score to balance the observed baseline characteristics based on the Inverse Probability Treatment Weighting (IPTW). The propensity scores were calculated based on the pregnant women’s ages at delivery, pregnancy complications, infertility treatments, delivery histories, smoking during pregnancy, alcohol use during pregnancy, body mass index before pregnancy, annual household incomes, and education levels, using a logistic regression model. Weighted logistic regression analyses were conducted to evaluate the association between KE use during the first and second trimester of pregnancy and the risk of adverse perinatal outcomes, including cesarean section, preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA), and low Apgar scores ( < 7). Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using logistic regression. Women who used acetaminophen served as the reference group in all analyses.

Results: Among women who used KE or acetaminophen during the first and second trimester of pregnancy, the prevalence of cesarean section, PTB, LBW, SGA, and low Apgar scores at 5 minutes was 23.0%, 5.6%, 8.3%, 3.9%, and 0.7%, or 24.2%, 5.1%, 7.6%, 3.6%, and 0.7%, respectively. Weighted logistic regression analyses indicated that KE use was not significantly associated with increased risks of caesarean section (OR, 0.95; 95% CI, 0.75–1.21), PTB (OR, 0.99; 95% CI, 0.63–1.56), LBW (OR, 1.03; 95% CI, 0.71–1.48), SGA (OR, 0.97; 95% CI, 0.57–1.64), and low Apgar scores at 5 minutes (OR, 0.88; 95% CI, 0.26–3.01).

Conclusions: There was no statistically significant association between KE use during the first and second trimester of pregnancy and adverse perinatal outcomes.