Women with inflammatory bowel disease have an increased time to pregnancy, which indicates reduced fertility among that population, according to study results.
Sonia Friedman, MD, of the division of gastroenterology at Brigham and Women’s Hospital, and colleagues wrote that many factors that come along with IBD are believed to have an impact on fertility, but previous studies on the subject have been skewed because voluntary childlessness is more common among women with IBD compared with the general population.
“This is the first study to examine waiting time to pregnancy, as a proxy for fertility, in a large cohort of women with IBD compared to women in the general population,” they wrote. “Importantly, this is the only study to evaluate patients actively trying to conceive so that our measurement of fertility is not confounded by the high rate of voluntary childlessness seen in women with IBD.”
Researchers analyzed data from the Danish National Birth Cohort comprising 92,274 pregnant women recruited from 1996 to 2002. The women who had actively been trying to conceive reported their time to pregnancy in a phone interview at about 16 weeks of gestation. Investigators compared the time to pregnancy in women with and without IBD.
The analysis included data from 74,471 pregnancies in women without IBD; 340 in women with ulcerative colitis and 206 in women in Crohn’s disease.
Compared with non-IBD pregnancies, the adjusted relative risk ratios for time to pregnancy of more than 12 months in women with IBD was 1.28 (95% CI, 0.99–1.65); 1.1 (95% CI, 0.8–1.51) in women with UC and 1.54 (95% CI, 1.03–2.3) in women with CD.
The risk was highest among women with CD who underwent surgery prior to conception (adjusted relative risk = 2.54; 95% CI, 1.39–4.65).
Friedman and colleagues wrote that their findings may be related to the disease or to factors closely related to it, such as the medications used to treat it, and called for more studies to explore their findings.
“It is hoped that these results will inform decisions regarding expediting infertility treatments in patients with IBD and timing of surgery in CD,” they wrote. Future research will hopefully elucidate the mechanism of decreased fertility in IBD as well as which surgeries most affect the time to pregnancy.” – by Alex Young
Disclosures: The authors report no relevant financial disclosures.