Higher Risk for CRC Seen in Adults Exposed to Bendectin In Utero

TUESDAY, March 28, 2023 (HealthDay News) — Adults exposed in utero to the antiemetic Bendectin (doxylamine/pyridoxine/dicyclomine), prescribed during pregnancy in the 1960s, have an increased risk for colorectal cancer (CRC), according to a study published online March 10 in JNCI Cancer Spectrum.

Caitlin C. Murphy, Ph.D., M.P.H., from the University of Texas Health Science Center at Houston School of Public Health, and colleagues examined the association between in utero exposure to Bendectin and the risk for CRC in adult offspring (aged 18 years and older) from the Child Health and Development Studies multigenerational cohort, which included 14,507 mothers and 18,751 liveborn offspring.

Overall, about 5 percent of offspring were exposed to Bendectin in utero. The researchers found that exposed offspring had a higher risk for CRC compared with unexposed offspring (adjusted hazard ratio, 3.38). For offspring exposed and unexposed to Bendectin, the incidence rates of CRC were 30.8 and 10.1 per 100,000, respectively.

“Our findings suggest medications prescribed to pregnant women in the 1960s may, in part, contribute to recent increases in incidence rates of CRC. As the burden of CRC continues to increase in the U.S. and worldwide, well-conducted experimental studies will be critical to clarify these findings and identify mechanisms of risk,” the authors write. “Testing for associations with in utero exposure to dicyclomine-containing medications still used during pregnancy may also be warranted.”

Two authors disclosed financial ties to the biopharmaceutical industry.