A review of the literature looked at the clinical basis for restricting the caffeine intake of mothers on fetal, neonatal and pregnancy outcomes41. After a thorough search of databases for published or unpublished studies, randomised controlled trials, including quasi-randomised trials and cross over studies, the authors identified a single study that met their criteria, thus highlighting the lack of research in this area. The authors selected one Danish study meeting the criteria for a controlled study: women less than 20 weeks pregnant were randomly assigned to drinking caffeinated instant coffee (568 women) or decaffeinated instant coffee (629 women). The study found that reducing the caffeine intake of regular coffee drinkers during the second and third trimester by an average of 182mg/day (approximately 2 regular cups of coffee) did not affect birth weight or length of gestation. According to the study, there is insufficient data to confirm or refute the effectiveness of caffeine avoidance on birth weight or other pregnancy outcomes and high-quality, double-blind randomised controlled studies are needed to determine whether caffeine has any effect on pregnancy outcomes41.
Official recommendations for caffeine intake during pregnancy
EFSA in their ‘Scientific Opinion on Caffeine’, published in 2015, advised that pregnant women should limit their caffeine intake to 200mg per day5.
This is in line with the UK’s NHS42 and the March of Dimes in the USA43, who both advise an upper limit for pregnant women of 200mg of caffeine* per day from all sources.
*A regular cup of coffee contains approximately 75mg caffeine.