Effects of restricted caffeine intake by mother on fetal, neonatal and pregnancy outcomes.
Level 1 - systematic review of randomized trials
Systematic review of randomized controlled trials
PubMed 26058966 · doi:10.1002/14651858.CD006965.pub4
What was done
Authors conducted a Cochrane systematic review searching the Cochrane Pregnancy and Childbirth Group's Trials Register (January 2015) and bibliographies for randomized and quasi-randomized trials evaluating caffeine restriction versus unrestricted caffeine or placebo in pregnant women. Two authors independently selected studies, extracted data, assessed risk of bias, and graded evidence quality.
What was found
Two studies met inclusion criteria, but only one trial contributed outcome data (568 women receiving caffeinated instant coffee vs. 629 receiving decaffeinated instant coffee). Reducing caffeine intake by an average of 182 mg/day during the second and third trimesters among regular coffee drinkers (3+ cups/day) resulted in: - Birthweight: mean difference 20.00 g (95% CI -48.68 to 88.68; 1 study, 1,197 participants; low quality evidence) - Preterm birth: risk ratio 0.81 (95% CI 0.48 to 1.37; 1 study, 1,153 participants; low quality evidence) - Small-for-gestational age: risk ratio 0.97 (95% CI 0.57 to 1.64; 1 study, 1,150 participants) Neither study reported on low birthweight, first-trimester fetal loss, perinatal mortality, fetal hypoxia, fetal tachycardia, or other maternal and neonatal outcomes.
Why it matters
Despite common recommendations to limit caffeine during pregnancy, randomized trial evidence is extremely sparse, providing insufficient proof to confirm or refute clinical benefits or harms of caffeine restriction.
Limits
Only one study contributed data to the analysis, and both included studies had moderate risk of bias. Sample sizes and wide confidence intervals led to low-quality GRADE ratings. Key outcomes including miscarriage, perinatal mortality, and fetal distress were not reported.
Cited by
- context The World Health Organization recommends that pregnant women consuming more than 300 mg of caffeine per day reduce their intake.