Periconceptual Caffeine Intake and Adverse Pregnancy Outcomes: Results From the nuMoM2b Cohort

Objective To determine the association of self‐assessed caffeine consumption with adverse pregnancy outcomes (APO). Design Secondary analysis of births in the Nulliparous Pregnancy Outcomes Study: Monitoring Mothers‐to‐be (nuMoM2b). Caffeine intake was assessed by the self‐reported Food Frequency Questionnaire reflecting consumption in the three months prior to the first trimester visit. Setting nuMoM2b was a prospectively collected cohort. Population This is a large US‐based cohort of pregnant patients. Methods High caffeine intake was defined as ≥ 200 mg/day. Logistic models assessed associations between high intake and APO, adjusted for confounders. We also grouped caffeine intake in 50 mg increments and tested whether increased consumption was associated with increased odds of APO. Main Outcome Measures APO were defined as a composite of intrauterine foetal demise > 20 weeks' gestation, hypertensive disorders of pregnancy, preterm birth and small for gestational age infant. Results The primary analysis included 7345 participants with live births or pregnancy loss > 20 weeks' gestation, for whom the median daily caffeine intake was 63.28 mg/day. 841 (11.4%) of patients had high intake and 2168 (29.5%) had an APO. When adjusted for confounders, high intake was not associated with increased odds of APO (aOR 0.99, 95% CI 0.84–1.16), nor was it associated with any individual APO. We found no significant increased odds of APO per 50 mg increase in caffeine intake. Conclusions High caffeine intake assessed in the periconceptual period was not associated with the risk of APO. Further research exploring biomarkers and longitudinal childhood outcomes is needed to clarify limitations with regard to intake.