Having a healthy pregnancy while managing Crohn’s disease is possible, but it requires careful preparation and coordination between medical specialists. A proactive, planned approach prioritizes maintaining disease inactivity throughout all stages for the best outcome for both mother and baby. Pre-conception counseling with a gastroenterologist and an obstetrician is a necessary first step to evaluate the current disease state, review medications, and establish a clear management strategy. Achieving and sustaining remission is essential, as active inflammation poses the greatest risk to maternal and fetal health.
Crohn’s Disease and Conception
Active inflammation from Crohn’s disease can temporarily reduce the ability to conceive in both women and men. For women, systemic inflammation may affect ovarian reserve, potentially decreasing Anti-Müllerian hormone (AMH) levels, an indicator of egg supply. Inflammation within the pelvic area can also lead to scarring around the fallopian tubes, physically impeding the egg’s journey to the uterus.
Prior pelvic surgery, such as proctocolectomy with ileostomy or the creation of an ileal pouch-anal anastomosis (J-pouch), can increase the risk of infertility due to scar tissue formation. Newer laparoscopic techniques may result in fewer adhesions and a lower impact on fertility compared to older procedures. For men, active disease or poor nutrition can temporarily reduce sperm count and motility, though this often improves once the disease is brought under control.
The most effective way to optimize the chances of a healthy conception is to achieve deep remission before attempting pregnancy. Experts recommend women be in clinical and endoscopic remission for a minimum of three to six months prior to conception. Conceiving while the disease is active doubles the risk of it remaining active throughout the pregnancy, severely impacting maternal and fetal health.
Maintaining Disease Remission During Pregnancy
Maintaining disease inactivity during pregnancy is the single most important factor for a healthy outcome. Active Crohn’s disease during gestation is associated with a significantly increased risk of complications, including miscarriage, stillbirth, and adverse birth outcomes. These risks are primarily driven by the inflammation itself, not the medications used to control it.
If conception occurs during a flare, the disease has a high chance of worsening or remaining active throughout the subsequent trimesters. Active inflammation compromises the mother’s ability to absorb nutrients, leading to malnutrition and anemia, which directly affect fetal development. This results in a higher likelihood of preterm birth (before 37 weeks) and having a baby with a low birth weight or who is small for gestational age.
Disease activity is generally unpredictable during pregnancy; some women improve, others experience a flare, and many remain stable. Monitoring for inflammation is essential due to the serious risks of active disease, often using blood markers like C-reactive protein (CRP) or fecal calprotectin stool tests. Proactive monitoring helps the medical team identify and treat potential flares quickly, preventing inflammation from escalating.
Evaluating Medication Safety for Mother and Fetus
Most modern Crohn’s treatments are safe to continue during pregnancy and should be maintained to prevent a disease flare. Medications like 5-aminosalicylates (5-ASAs), corticosteroids (prednisone), and thiopurines (azathioprine or 6-mercaptopurine) are generally considered safe for use throughout pregnancy. The risk of an untreated flare far outweighs the potential risk from these necessary maintenance medications.
Biologic therapies, such as anti-TNF agents (infliximab, adalimumab), vedolizumab, and ustekinumab, are usually continued to protect the mother’s health. Some biologics are large antibody molecules that may cross the placenta via active transport, primarily during the second and third trimesters. This transfer can lead to higher drug levels in the newborn’s cord blood. Certolizumab pegol is an exception, as its unique structure results in markedly lower placental transfer, making it a preferred option for some patients.
Methotrexate requires strict pre-conception planning and must be discontinued at least three to six months before attempting conception for both men and women due to its association with birth defects. Pre-conception consultation with a multidisciplinary team, including a gastroenterologist and a Maternal-Fetal Medicine specialist, is vital to review the entire drug regimen and make necessary adjustments well in advance. This planning ensures the mother stays in remission on the safest possible combination of treatments throughout the pregnancy.
Labor, Delivery, and Newborn Risks
For most women in remission, the mode of delivery is determined by routine obstetrical factors, as a vaginal birth is often preferred and does not typically worsen Crohn’s disease. However, specific features may necessitate a planned Cesarean section (C-section) to protect the anal sphincter muscle. A C-section is generally recommended for women with active perianal disease, such as abscesses or recto-vaginal fistulas, to avoid severe tears that could compromise continence.
A prior ileal pouch-anal anastomosis (J-pouch) may also be a relative indication for a C-section due to a theoretical risk of anal sphincter damage during vaginal delivery that could impair pouch function. Women with healed perianal disease can often attempt a vaginal delivery, but the decision is made on a case-by-case basis. The overall risk of passing Crohn’s disease to the child is low, but present; if one parent has Crohn’s, the child has an estimated 7% to 9% lifetime risk of developing the condition.
Following delivery, breastfeeding is encouraged, as most Crohn’s medications are compatible with nursing. The majority of drugs, including 5-ASAs, thiopurines, and biologics, transfer into breast milk at very low levels that are not harmful to the infant. Continued use of maintenance medications during the postpartum period is important to reduce the risk of a maternal flare.