Study of Vitamin B6--Before and After

Vitamin B-6, an old remedy for morning sickness, is getting another look. According to a report by Iowa researchers just published in the journal Obstetrics & Gynecology, Vitamin B-6 can help reduce the nausea and vomiting experienced by 50% or more of pregnant women.

Nearly 50 years ago, researchers suggested that B-6 might help quell morning sickness, which is most common during the first trimester but sometimes occurs throughout pregnancy. In 1979, the American Medical Assn. said there was no scientific evidence that B-6 worked for nausea.

The Iowa researchers are again suggesting that it might help. In a study of 59 queasy pregnant women, 31 took B-6 for three days (a 25-milligram tablet every 8 hours); the other 28 took placebo pills on the same time regimen. Women with mild to moderate nausea who took the B-6 didn’t notice much difference, but those with severe nausea reported improvement. Half the women who had vomiting got relief from the B-6.

Researchers aren’t sure how the vitamin works. Dr. Jennifer Niebyl, professor and head of obstetrics and gynecology at the University of Iowa and a co-researcher of the study, says B-6, found in bananas, potatoes and other foods, is essential to help metabolize fats, carbohydrates and amino acids. Levels of the vitamin generally fall during the second and third trimesters, but Niebyl says the decrease is not related to morning sickness.

But a local gynecologist familiar with the study isn’t convinced that B-6 deserves another chance. The number of women involved in the study is relatively small, says Dr. Gerald S. Bernstein, USC professor of obstetrics and gynecology. And it is difficult, he adds, to measure nausea objectively. “I don’t think (the study) proves anything at all,” adds Bernstein, noting the need for more research. Niebyl encourages women to try a variety of self-treatment approaches for morning sickness before resorting to vitamin therapy. Munching soda crackers, eating small and frequent meals and avoiding spicy foods can help minimize nausea and vomiting, she says. If those routes fail, she adds, women should consult their obstetricians before starting vitamin B-6 treatment.

Or they can just let nature take its course.