From swollen ankles to the infamous craving for peanut butter and pickles, pregnancy rites of passage have been well documented. There's one tradition, however, most expectant mothers could do without: nausea and vomiting.
Nausea and vomiting affect between 50 and 90 percent of pregnant women, according to researchers at the University of Texas. Metoclopramide, a dopamine blocker, is a prescription medication that can help relieve stomach symptoms.
In a study published today in the Journal of the American Medical Association, researchers from Denmark confirmed that taking this medication during pregnancy does not increase the risk of major birth defects, spontaneous abortion, or stillbirth.
Researchers were intrigued to find that metoclopramide use was common among pregnant women, even before a study of this size had been conducted, says study author Björn Pasternak, M.D., Ph.D., a researcher at the the Statens Serum Institut in Copenhagen.
Though many pregnant women in the throes of morning sickness want a medical solution, there wasn't a complete picture of the drug's safety until now. “This is by far the largest study on metoclopramide safety in pregnancy...It confirms previous results and adds to these results by providing estimates of risk with very high precision,” Pasternak says.
Researchers looked at data from more than a million pregnancies in Denmark between 1997 and 2011. Of the women included in the analysis, more than 40,000 were exposed to metoclopramide at some point during their pregnancy. From birth data, researchers concluded that exposure to metoclopramide is not linked to any significant increase in the risk of fetal death or birth defects, or secondary outcomes like low birth weight or premature birth.
In some cases, the risk seemed to be lower in the exposed population: 2.5 percent of babies born to mothers exposed to metoclopramide during pregnancy developed a congenital malformation during the first year of life, compared to 2.6 percent of babies born to mothers who had not taken metoclopramide.
The U.S. Food and Drug Administration approved the use of metoclopramide more than 30 years years ago, though in 2009 the organization added a black box warning for chronic use because of an increased risk of developing tardive dyskinesia, a slow-paced movement disorder.
Nausea No More?
Pasternak says that 10 to 15 percent of women who experience nausea and vomiting during pregnancy require treatment with some form of medication. For them, the reassurance that metoclopramide doesn’t increase the risk of birth defects will hopefully make taking the treatment easier.
Moreover, the medication won't ruin a pregnant woman's day. Those who receive medical treatment for morning sickness experience significant relief with only a small, or no, impact on their daily activities, Pasternak says.
“Nausea severity can vary from just a bit of morning sickness to severe hyperemesis with weight loss,” Pasternak says. Metoclopramide is usually prescribed to women for whom an antihistamine or vitamin B6 treatment course has failed, the study authors wrote.
For a more natural fix, the Office of Women’s Health, of the U.S. Department of Health and Human Services, recommends eating six to eight smalls meals a day and avoiding greasy foods.
“It is important to continue studying medication safety in pregnancy,” Pasternak says. “Keep in mind that there is no or very limited safety information [for pregnant women] for many of the drugs on the market.”