Pregnancy Problems Tied to CaffeineToo much caffeine during pregnancy may increase the risk of miscarriage, a new study says, and the authors suggest that pregnant women may want to reduce their intake or cut it out entirely.
Many obstetricians already advise women to limit caffeine, though the subject has long been contentious, with conflicting studies, fuzzy data and various recommendations given over the years.
The new study, being published Monday in the American Journal of Obstetrics & Gynecology, finds that pregnant women who consume 200 milligrams or more of caffeine a day — the amount in 10 ounces of coffee or 25 ounces of tea — may double their risk of miscarriage.
Pregnant women should try to give up caffeine for at least the first three or four months, said the lead author of the study, Dr. De-Kun Li, a reproductive and perinatal epidemiologist at the Kaiser Permanente Division of Research in Oakland, Calif.
Now, having reviewed the new study, the March of Dimes plans to change its message, to advise women who are pregnant or trying to conceive to limit their daily caffeine intake to 200 milligrams or less, said Janis Biermann, its senior vice president of education and health promotion.
Dr. Li said the study answered an important question that previous research had left unresolved. Women who have morning sickness are less likely to miscarry than those who do not, possibly because the same hormonal changes that cause nausea and vomiting contribute to a healthy pregnancy. But some researchers said morning sickness could lead to confusing results in caffeine studies. These researchers argued that because they feel ill, some women may consume less caffeine. That tendency may make it appear that they are less likely to miscarry because they avoid caffeine, when the reason is actually that they began with healthier pregnancies.
Dr. Li said he and his colleagues had determined that the risk from caffeine was real and could not be explained away by different rates of morning sickness. source