Pregnant women who drink two or more cups of coffee a day have twice the risk of
having a miscarriage as those who avoid caffeine. U.S researchers said on
January 21, 2008. They said the study provides strong evidence that high doses
of caffeine during pregnancy — 200 milligrams or more per day or the equivalent
of two cups of coffee — significantly increase the risk of miscarriage. And
they said the research may finally put to rest conflicting reports about the
link between caffeine consumption and
miscarriage.

"Women who are
pregnant or are actively seeking to become pregnant should stop drinking coffee
for three months or hopefully throughout pregnancy," said Dr. De-Kun Li of
Kaiser Permanente Division of Research, whose study appears in the American
Journal of Obstetrics and Gynaecology. "There has been a lot of uncertainty
about this," Li said in a telephone interview. "There was no firm advice from
professional societies to say what a pregnant woman should do about caffeine
intake."

Li said anywhere from
15 to 18 studies have found a link between caffeine use during pregnancy and
miscarriage. But that association has been clouded by the fact that many
pregnant women avoid caffeine because it makes them nauseated, which could skew
the results. Li and colleagues took pains to control for that possibility. Their
study involved 1,063 pregnant women who were members of the Kaiser Permanente
health plan in San Francisco from October 1996 through October 1998.

Women in the group never
changed their caffeine consumption during pregnancy. What they found was women
who consumed the equivalent of two or more cups of regular coffee or five
12-ounce cans of caffeinated soda — were twice as likely to miscarry as
pregnant women who avoided caffeine. This risk appeared to be related to the
caffeine, rather than other chemicals in coffee, because they also saw an
increased risk when the caffeine was consumed in soda, tea, and hot chocolate.

Li said many researchers think
caffeine is harmful because it stresses the foetus’ immature metabolism. It may
also decrease blood flow in the placenta, which could harm the foetus. "To me,
the safe dose is zero," Li said. "If you really have to drink coffee, try to
limit it to one cup or at the most two cups." Or better yet, switch to
decaffeinated beverages, he added. Based on the findings, Dr. Tracy Flanagan,
director of women’s health at Kaiser Permanente Northern California, said
pregnant women should think about limiting coffee to one cup a day, and they
might want to cut it out entirely. "So many causes of miscarriage are not
controllable," she said in a telephone interview. "This is an opportunity to do
something active."

Via Times of India