There is insufficient scientific evidence to warrant advising women to stop drinking coffee or tea during pregnancy. It may benefit mothers to know that the effects of caffeine last longer in the third trimester. And that soft drinks, chocolate, and other sources add to caffeine intake.
New research suggests an eye out for excess, but no need to obsess over moderate coffee and tea drinking. Moderate is usually described as not more than three cups a day (my mug holds 1.75 cups). Excess would be more than six cups a day. The Generation R Study in the Netherlands found six cups or more of coffee per day increased the risk of small-for-gestational-age babies.
A 2010 meta-analysis of findings reported over 30 years found “no important association between caffeine intake during pregnancy and preterm birth”. The National Birth Defects Prevention Study found “no convincing evidence” of an association between mothers’ coffee or tea drinking and any of several birth defects. A Cochrane Review found insufficient evidence to suggest that not drinking coffee prevented low birth weight or preterm birth.
Beginnings Pregnancy Guide currently mentions avoiding caffeine as a way to feel less tired:
“Cut down on coffee, tea, and soft drinks. They wash nutrients out of your body before you can use them. “ Book 1 page 19
I found no evidence to suggest adding or changing the information. Moderate caffeine intake is a low priority for pregnancy health education.
Bakker R, Steegers E AP, Obradov, A. et al. (2010). Maternal Caffeine Intake from coffee and tea, fetal growth, and the risks of adverse birth outcomes. American Journal of Clinical Nutrition 91:1691-8.
Browne ML, Hoyt AT, Feldkamp ML. et al. (2011). Maternal caffeine Intake and Risk of Selected Birth Defects in the National Birth Defects Prevention Study. Birth Defects Research (Part A) 91: 93-101.
Jahanfar S. & Sharifah H.(2010). Effects of restricted caffeine intake by mother on fetal, neonatal and pregnancy outcomes (Review). The Cochrane Library 3. http://www.thecochranelibrary.com
Maslova E, Bhattacharya S, Lin S& Michels KB. (2010). Caffeine consumption during pregnancy and risk of preterm birth: a meta-analysis. American Journal of Clinical Nutrition 92: 1120-32.