Heartburn medications appear safe in pregnancy

Heartburn in pregnancy is common, beginning as early as the first trimester. But doctors have worried that medications to treat the condition, called proton-pump inhibitors, may not be safe in pregnancy. A new study shows that the drugs, especially Prilosec, appear to be safe for pregnant women and women who may become pregnant.

Researchers in Denmark examined a large database to find 5,082 cases in women who were exposed to proton-pump inhibitors at some time during the period of four weeks prior to pregnancy through the first trimester. They found no significant differences in birth defects among the women who took proton-pump inhibitors (PPIs) compared with the women who didn’t. One exception, however, was during the four weeks prior to pregnancy. During this period, exposure to the proton-pump inhibitors -- except Prilosec, or omeprazole -- increased the risk of major birth defects by 39%.

The authors of the study dismissed this finding as biologically implausible because the medications do not stay in the body for more than a few hours. But the risk of pre-pregnancy exposure cannot be ruled out, said the authors of an accompanying editorial. It could be that the underlying condition that requires use of the medications may increase the risk of birth defects or that the medications cause sustained changes in micronutrients that raise the risk of birth defects.

While the study is reassuring that proton-pump inhibitors are likely safe during pregnancy, “Until we have a better understanding of what might explain this latter finding [an increased risk prior to conception], it may be prudent to consider omeprazole to be the PPI of choice when PPI treatment is clearly needed for women of childbearing potential and particularly for those who are planning to become pregnant,” the authors of the commentary wrote. The paper was published Wednesday in the New England Journal of Medicine.

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