A northern California company says it has confirmed a link between caffeine and miscarriage. The Kaiser Permanente study suggests that women avoid caffeine altogether while pregnant, but especially in the first trimester, and perhaps even while they're trying to get pregnant.
Researchers found that pregnant women who consumed two or more cups of coffee (or 200mg of caffeine) each day had more than double the risk of a miscarriage when compared to pregnant women who had no caffeine. And the risk seems to be the same whether you get your caffeine from coffee, tea, or sodas.
De-Kun Li, MD/PhD, of Kaiser Permanente says, "Regardless of where the caffeine came from, as long as your intake went above 200 milligrams, the risk of miscarriage is increased. If a mother's blood vessel contracts too severely, the theory is that it can reduce blood flow to placenta."
Dr. De-Kun Li was the lead researcher who studied more than 1,000 Bay Area patients from early pregnancy until birth. He found that even the women who drank less than a cup a day had a miscarriage rate higher than women who didn't have any caffeine while pregnant. The theory behind the study is that a high dose of caffeine may constrict a mother's blood vessels. Doctors say coffee may also pose a risk of miscarriage because it may be difficult for a fetus to metabolize caffeine.
Women, of course, have no control over some things (like chromosomes) that can cause miscarriage, but they can control how much caffeine they consume. And, as this study showed, that small change could make a huge difference.