Caffeine consumption during pregnancy and risk of preterm birth a meta-analysis

Background The effect of caffeine intake during pregnancy on the risk of preterm delivery has been studied for the past 3 decades with inconsistent results Objective We performed a meta analysis ex miming the association between caffeine consumption during pregnancy and risk of preterm birth Design We searched MEDLINE and EMBASE articles published between 1966 and July 2010 cross referenced reference lists of the retrieved articles and identified 15 cohort and 7 case control studies that met inclusion criteria for this meta analysis Results The combined odds ratios (ORs) obtained by using fixed effects models for cohort studies were 1 11(95% CI 096 1 28) 110 (95% CI 1 01 1 19) and 1 08(95% CI 093 1 27) for risk of preterm birth comparing the highest with the lowest level of caffeine intake (or no intake) (mg/d) during the first second and third trimesters respectively Results for the case control studies yielded no associations for the first (OR 1 07, 95% CI 084 1 37) second (OR 117 95% CI 094 1 45) or third (OR 094 95% CI 079 1 12) trimesters No overall heterogeneity was found by region publication decade exposure and outcome assessment caffeine sources or adjustment for confounding, which was largely driven by individual studies Conclusion In this meta analysis we observed no important association between caffeine intake during pregnancy and the risk of preterm birth for cohort and case-control studies Am J Clin Mar 2010 92 1120-32