Ulcerative colitis (UC) is a chronic inflammatory bowel disease affecting the lining of the large intestine. Since many women with UC are diagnosed during their childbearing years, managing the condition during pregnancy raises concerns about fertility, disease activity, and treatment safety. With careful planning and collaborative care between a gastroenterologist and an obstetrician, most women with UC can have healthy pregnancies. The most important factor for a successful pregnancy is achieving and maintaining disease remission.
Effects of Ulcerative Colitis on Conception and Disease Activity
Ulcerative colitis generally does not impair conception when the disease is in remission; fertility rates are comparable to the general population. Active, moderate-to-severe inflammation, however, can reduce fertility due to systemic illness or malnutrition. Women who have undergone major pelvic surgery for UC, such as the creation of an ileal pouch-anal anastomosis (J-pouch), may also experience lower conception rates due to scar tissue formation around the fallopian tubes.
The course of UC activity is predictable based on the disease status at conception. Approximately 80% of women who conceive while in remission will remain in remission throughout the pregnancy. Conversely, a woman who conceives during an active flare has a high probability (around 65%) of remaining active or experiencing worsening symptoms. Flares are most common in the first and second trimesters and in the immediate postpartum period.
Risks Associated with Active UC During Pregnancy
Active, uncontrolled ulcerative colitis poses the greatest risk to both the mother and the developing fetus. Systemic inflammation and nutritional deficits associated with a flare are the main drivers of adverse outcomes. Active disease increases the risk of preterm birth (delivery before 37 weeks of gestation), low birth weight, or the infant being small for gestational age.
Uncontrolled inflammation can also increase the risk of miscarriage or stillbirth, correlating strongly with the severity of the maternal disease. For the mother, an active flare may necessitate hospitalization, high-dose steroid therapy, or emergency surgery, which adds significant risk. The goal of medical management is to minimize these risks by keeping the disease inactive.
Navigating UC Medication Safety
The risk of uncontrolled inflammation to the fetus is far greater than the risk posed by most UC medications. Stopping effective treatment without medical consultation is strongly discouraged, as maintaining remission offers the best outcome. Most common UC therapies are safe to continue throughout all trimesters.
Medication Safety Status
- Aminosalicylates (5-ASAs), such as mesalamine and sulfasalazine, are generally safe. Women taking sulfasalazine must increase folic acid supplementation (often to 2 milligrams daily) to counteract its effect on folate absorption.
- Corticosteroids (e.g., prednisone) are reserved for treating flares and used cautiously, as prolonged use is associated with a slightly increased risk of gestational diabetes and low birth weight.
- Biologic therapies, including anti-TNF agents like infliximab and adalimumab, are widely considered safe, though they cross the placenta more readily in the third trimester. Certolizumab pegol is often favored due to minimal placental transfer.
- Immunomodulators like azathioprine and 6-mercaptopurine can be safely continued if needed to maintain remission.
- Medications like methotrexate and Janus kinase (JAK) inhibitors (e.g., tofacitinib) are not recommended and must be discontinued before conception.
Delivery Method and Postpartum Management
The mode of delivery is primarily determined by standard obstetric considerations for women with ulcerative colitis in remission. Vaginal delivery is considered safe and is generally the preferred method. A cesarean section is typically only necessary for specific complications, such as active perianal disease (a contraindication for vaginal delivery) or a pre-existing ileal pouch-anal anastomosis (J-pouch).
The postpartum period carries a significant risk of a UC flare; approximately one-third of women relapse within the first year after delivery, most commonly within the first three to six months. Continuing medication after delivery is paramount to prevent this relapse. Most UC medications are compatible with breastfeeding, as drug levels in breast milk are extremely low. Biologic agents, 5-ASAs, and immunomodulators can be safely continued while nursing without adjusting the timing of breastfeeding around the medication dose.