Are Pain Killers Linked to Birth Defects

Ibuprofen, aspirin, and naproxen are commonly used NSAIDs for pain relief, headaches and cold and flu-symptoms. As such they are generally available over-the-counter. A study, published in 2005 in the American Journal of Obstetrics and Gynecology, found that approximately 25% of women use NSAIDs during pregnancy.

Here’s the problem: these over-the-counter pain medications – most notably aspirin, Advil and Aleve, may be associated with an increased risk of birth defects when taken by pregnant women.

In a recent publication in the American Journal of Obstetrics and Gynecology, non-steroidal anti-inflammatory drugs (NSAID) found that although NSAID use in early pregnancy did not appear to be a major risk factor for birth defects, there were some associations that gave researchers cause for concern. This study was undertaken to investigate associations previously reported by others in small scale studies. The study was funded by the U.S. Centers for Disease Control and Prevention. Data was analyzed from the National Birth Defects Prevention Study (NBDPS), an ongoing surveillance study created to identify infants with major birth defects and determine genetic and environmental risk factors.

The current study found that 22.6% of women in the NBDPS reported the use of NSAIDs during the first trimester, consistent with the previous report of approximately 25%. Of the women exposed to NSAIDs during the first trimester, 3,173 (70%) women reported exposure to NSAIDs during the first trimester of pregnancy and 1,452 (30%) used NSAIDs “as needed” during a period of time that included the first trimester. The most used NSAID among users was ibuprofen followed in order of decreasing prevalence by aspirin, naproxen and other NSAIDs. 15,860 women were not exposed to NSAIDs during the first trimester of pregnancy.

Though most birth defects were not found to be associated with NSAID use, there were some birth defects in which NSAIDs presented a low to moderate increase in risk. These birth defects include anopthalmia/microphthalmia, amniotic bands/limb body wall defects, pulmonary valve stenosis, transverse limb deficiencies, oral clefts, and neural tube defects, which were found to be associated with ibuprofen, aspirin, and naproxen use. The type of oral cleft and neural tube defects varied between specific NSAIDs.

Spina bifida was associated with ibuprofen use; anencephaly/craniorachischisis was associated with aspirin; and encephalocele was associated with both aspirin and naproxen use. Similar associations were seen when women who reported using NSAIDs “as needed” were analyzed separately from all women.

It is important to note that further research is required to determine the amount of medication taken that results in birth defects, and whether warnings are necessary on labels. As the relative risks are still low to moderate, the risk of birth defects and the need for NSAIDs during pregnancy needs to be assessed by a woman’s physician. But really, from a cost/benefit perspective, these painkillers are not live saving. If there is even a little risk, isn’t it worth conveying the news loudly to young woman that they may be risking the health of their unborn child?

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