Document Type


Publication Date



This article has been peer reviewed. It is the authors' final version prior to publication in Birth Defects Research Part B-Developmental and Reproductive Toxicology.

Volume 92, Issue 2, April 2011, Pages 152-187.

The published version is available at DOI: 10.1002/bdrb.20288, Copyright © John Wiley & Sons, Inc.


A risk analysis of in utero caffeine exposure is presented utilizing epidemiological studies and animal studies dealing with congenital malformation, pregnancy loss, and weight reduction. These effects are of interest to teratologists, because animal studies are useful in their evaluation. Many of the epidemiology studies did not evaluate the impact of the "pregnancy signal," which identifies healthy pregnancies and permits investigators to identify subjects with low pregnancy risks. The spontaneous abortion epidemiology studies were inconsistent and the majority did not consider the confounding introduced by not considering the pregnancy signal. The animal studies do not support the concept that caffeine is an abortafacient for the wide range of human caffeine exposures. Almost all the congenital malformation epidemiology studies were negative. Animal pharmacokinetic studies indicate that the teratogenic plasma level of caffeine has to reach or exceed 60 µg/ml, which is not attainable from ingesting large amounts of caffeine in foods and beverages. No epidemiological study described the "caffeine teratogenic syndrome." Six of the 17 recent epidemiology studies dealing with the risk of caffeine and fetal weight reduction were negative. Seven of the positive studies had growth reductions that were clinically insignificant and none of the studies cited the animal literature. Analysis of caffeine's reproductive toxicity considers reproducibility and plausibility of clinical, epidemiological, and animal data. Moderate or even high amounts of beverages and foods containing caffeine do not increase the risks of congenital malformations, miscarriage or growth retardation. Pharmacokinetic studies markedly improve the ability to perform the risk analyses.

enc_Tables 1-5 7-11.pdf (64 kB)
Table 1: Evaluating the Allegation of Teratogenicity

enc_Table 6.pdf (224 kB)
Table 6: Summary of Animal Studies in Included in Caffeine Update Review

enc_Rev Caffeine Refs 1-2011.pdf (111 kB)

PubMed ID