A Danish study published in the Feb. 28 online New England Journal of Medicine suggests that a drug commonly used to treat severe morning sickness does not pose an increased risk for birth defects or other health problems to the fetus.
Researchers said the study does not prove that ondansetron — brand name Zofran – is risk-free. However, they do report that the study should reassure women who need the drug.
According to Associated Press, one in 10 pregnant women have nausea and vomiting bad enough to require medication. The condition, called hyperemesis gravidarum, recently made headlines when the Duchess of Cambridge, Kate Middleton, was hospitalized for severe morning sickness.
The study, led by Bjorn Pasternak, MD, PhD, of the Department of Epidemiology Research at Statens Serum Institut in Copenhagen, Denmark, used data from 608,385 pregnancies between 2004 and 2011. Researchers looked at nationwide health registries to compare the rates of miscarriage, stillbirth, preterm delivery, major birth defects or low birth weight babies among the women who took Zofran during their pregnancies and those who did not.
The study found no evidence of major birth-related problems in women who took Zofran. Of the women who took the morning sickness drug in the first trimester, just over 1 percent had a miscarriage, versus almost 4 percent of women who did not take the drug. In both groups, 3 percent of the mothers had a baby with a major birth defect.
Although researchers concluded that “ondansetron taken during pregnancy was not associated with a significantly increased risked of adverse fetal outcomes,” it should be noted that the study is observational, which means that it relies on a review of medical records.
The best kinds of studies for researching a drug’s benefits and risks are controlled clinical trials where patients are randomly assigned to take a medication or a placebo. Because it is considered unethical to conduct such studies on pregnant women, doctors in this case had to rely on records-based research.
Jennifer Wu, MD, an obstetrician/gynecologist at Lenox Hill Hospital in New York City told HealthDay the study was not ideal, but that the findings were reassuring.
“This is a drug we have been using for a while,” said Wu. “It can help keep women out of the hospital, and help keep them functioning on a day-to-day basis. “
Also weighing in on the study, Iffath Hoskins, MD, a high-risk pregnancy specialist at NYU Langone Medical Center and a spokeswoman for the American College of Obstetricians and Gynecologists, told Associated Press that the drug “is effective and safe. Nobody is giving you a gold star for suffering through this.”
Hoskins added that poor nutrition because of excessive vomiting can harm the mother and the fetus. However, she advised that women should try treating morning sickness with crackers, ginger ale and certain B vitamins and use Zofran or one of the other prescription anti-nausea medicines as a last resort.
“Whenever possible, nothing or simple is better” than a drug, especially in the first three months of pregnancy, she said.