A new study has found that pregnant women who consumed more than 200 milligrams of caffeine a day, equivalent to about two cups of coffee, had twice the risk of miscarriage as the women who consumed no caffeine at all. The findings are published in Monday’s Journal of Obstetrics and Gynecology.
The Kaiser study looked at 1,063 women in the early stage of pregnancy. Among women who consumed no caffeine, the miscarriage rate was 12.5 percent. In comparison, 25.5 percent of women who consumed more than 200 mg of caffeine a day miscarried. Although there was an increased risk for women who consumed fewer than 200 mg of caffeine a day, the lead investigator says the increase is not statistically significant.
Caffeine is dangerous during pregnancy, Li said, because it can cross through the placenta to the fetus and can be difficult for the fetus to metabolize the caffeine. Caffeine may influence cell development and decrease blood flow to the placenta, he added. If arteries are constricted it may restrict blood flow which can result in miscarriage.
Robert Barnes February 16, 2009