Associations between inflammatory bowel disease, medication use during pregnancy and rates of preterm delivery (PTD) subtypes in the Danish National Birth Cohort, 1996–2003.

HR, hazard ratio; CI, confidence interval; PTD, preterm delivery; PPROM, premature preterm rupture of membranes.

All estimates were adjusted for parity (0, 1, ≥2), socioeconomic status (6 categories: master’s degree or higher and currently employed, or leader of a business with ≥10 employees; bachelor’s degree and currently employed, or leader of a business with <10 employees; skilled worker (completed vocational training with apprenticeship) and currently employed; unskilled worker or unemployed (short-term); current student; unemployed (long-term)), pre-pregnancy BMI (<20, 20–25, >25), and smoking (non-smoker, smoker) and alcohol consumption (non-drinker, <1 drink/week, ≥1 drink/week) during pregnancy, in strata within the models.

^a Includes women with IBD who used internal corticosteroids or 5-ASA during pregnancy.

Associations between inflammatory bowel disease, medication use during pregnancy and rates of preterm delivery (PTD) subtypes in the Danish National Birth Cohort, 1996–2003.