Gestational Low-Dose Aspirin Does Not Increase Risk of IBD Flares in Women

Low-dose aspirin was not associated with increased risks of disease activity among pregnant women with inflammatory bowel disease (IBD), according to new findings presented at the American College of Gastroenterology (ACG) 2023 Annual Scientific Meeting in Vancouver, BC this week.

A team of investigators from the University of California, San Francisco (UCSF) reported findings from their tertiary academic care center showing that, despite approximately 3 in 10 pregnant women with IBD taking an aspirin dose of either 81 mg or 162 mg for the prevention of hypertensive disorders including preeclampsia, there were no differences in cumulative rate of IBD flare during pregnancy nor postpartum.

The investigators sought to evaluate the prevalence of low-dose aspirin treatment among pregnant women with IBD, as well as the effects of the treatment on IBD disease. They noted prior research published in The New England Journal of Medicine helped set low-dose aspirin recommendations for the prevention of conditions including eclampsia, preeclampsia and gestational hypertension in higher-risk patients during pregnancy.

“However, regular non-steroidal anti-inflammatory drug use raises concerns of increased disease activity in patients with IBD,” they noted.

Their analysis of patients treated at the academic center’s Maternal Fetal Medicine clinic from 2013 - 2022 noted the timing and dosage of prescribed low-dose aspirin. The team additionally sought IBD outcomes including disease flare—defined as IBD-related hospitalizations or surgeries, new treatment initiation, elevated fecal cal protein, or new active endoscopic disease—during pregnancy or at 6 months postpartum.

The analysis including 325 patients (median age, 34 years; 53% with ulcerative colitis) showed that 95 (29%) patients received low-dose aspirin during their pregnancy. Investigators observed an IBD flare rate of 24% among women who took aspirin, versus 26% among those who did not (P = .083).

The findings additionally showed that pregnant women with IBD on low-dose aspirin were more likely to give a preterm birth (21% vs 14%) and a cesarean delivery (51% vs 27%) than those who did not (P <.01).

Based on unavailable logistic regression analysis, the 162 mg dose of aspirin (odds ratio [OR], 2.77; 95% CI, 1.07 - 7.41) and an ulcerative colitis diagnosis (OR, 2.34; 95% CI, 1.39 - 4.02) were associated significantly increased risk of IBD flare.

In an interview with HCPLive during ACG 2023, study author Uma Mahadevan, MD, professor of clinical medicine at UCSF, discussed how the new findings impact current standard protocol for managing pregnancy-related risks in women with IBD.

Among the approximate 3 million individuals with IBD in the US, about half are women, and they almost all carry an IBD diagnosis during their childbearing years, Mahadevan said. Historically, women with IBD have significantly greater rates of pregnancy, labor and delivery complications than the general population.

“Most of these women generally are closely followed by their gastroenterologist,” Mahadevan said. “So ideally, when they go through pregnancy, they should not have any signs and symptoms of IBD. However, for women with ulcerative colitis, sometimes the first time they're diagnosed is during pregnancy, and what you're looking for is painful, bloody diarrhea, a higher degree of anemia than you would generally see in pregnancy, abdominal pain, and importantly, failure to gain weight.”

Mahadevan acknowledged the “somewhat controversial” data her team reported, noting that many patients with IBD are told to avoid aspirin due to the risk of triggering disease flares. The recommendation conflicts with another stating that women with IBD at high risk of preeclampsia take low-dose aspirin.

These findings set the record clear for both patients and clinicians in obstetrics and gastroenterology.

“What we would highlight is that women with inflammatory bowel disease should be followed as high risk,” Mahadevan said. “We know they have higher rates of hypertensive disorders of pregnancy, including preeclampsia. To reduce that risk, all of them should be started on low-dose aspirin...from about week 12 to week 36 of gestation, and they should be monitored for preeclampsia.”

References

1. ^{Yu A, Fenton CL, Wen T, Irani RA, et al. The Effect of Low-Dose Aspirin on Disease Activity in Pregnant Individuals with Inflammatory Bowel Disease. Paper presented at: ACG 2023 Annual Scientific Meeting. Vancouver, BC, Canada. October 20 – 25, 2023.}
2. ^{Nicolaides KH. Aspirin versus Placebo in Pregnancies at High Risk for Preterm Preeclampsia. N Engl J Med. 2017;377(24):2400. doi:10.1056/NEJMc1713798}