Antenatal Exposure to Opioids May Increase the Risk of Neural Tube Defects

Previous studies have suggested a link between opioid exposure and increased risk of certain congenital malformations.

In a recent case-control study, data was collected from mothers of babies with neural tube defects (n=305), other malformations (n=13,405), or no malformations (n=7125). Mothers who used opioids within the first two months of pregnancy were about twice as likely to have a child with a neural tube defect (NTD), particularly spina bifida, compared to women who did not use opioids. Among women taking opioids early in pregnancy, the risk of a having a baby with an NTD was relatively low, about 5.9 per 10,000 births, compared to 2.6 per 10,000 births among non-users.

Some caveats. Case-control studies may overestimate risk. They do not establish a cause-and-effect relationship; in fact, often other associated factors may modulate risk. Nonetheless, the prevalence of opioid use among young women is high; thus women must be informed of the potential risks associated with exposure. Although this study did not address the use of folic acid, one might also consider supplementation with folic acid (at least 1 mg daily) in women of reproductive age who are taking opioids.

Ruta Nonacs, MD PhD

Yazdy MM et al. Periconceptional use of opioids and the risk of neural tube defects. Obstet Gynecol 2013 Oct; 122:838.

Key Findings: Opioid Use and Neural Tube Defects (CDC)

Some Painkillers Tied to Certain Birth Defects in Study (HealthDay)