When you have inflammatory bowel disease (IBD)-whether it’s Crohn’s disease or ulcerative colitis-and you’re planning a pregnancy, the biggest question isn’t just can you get pregnant? It’s: can you stay safe while staying well?
For years, women with IBD were told to stop their meds before trying to conceive. Many did-and ended up in the hospital with flare-ups. The truth is, uncontrolled IBD is far more dangerous to your baby than the medications keeping you in remission. Active disease at conception triples your risk of preterm birth, doubles the chance of low birth weight, and increases stillbirth risk by 60%. That’s not a small risk. That’s the real threat.
What Medications Are Actually Safe During Pregnancy?
Let’s cut through the noise. Not all IBD drugs are created equal when it comes to pregnancy. Some are rock-solid safe. Others? Not so much.
Aminosalicylates (5-ASAs) like mesalamine and sulfasalazine are your go-to if you’re on maintenance therapy. The global consensus from the Helmsley PIANO registry, which tracked over 1,500 pregnancies, confirms they’re safe throughout all three trimesters. The Crohn’s & Colitis Foundation and ECCO both say: keep taking them. No changes needed.
But here’s the catch: not all mesalamine brands are the same. Asacol® and Asacol HD® use a coating called dibutyl phthalate (DBP). Animal studies and human case reports show this coating can cause genital malformations in male babies. If you’re on Asacol, switch to Lialda, Delzicol, or Apriso-none of these contain DBP. Your doctor should check your prescription before you even start trying.
Sulfasalazine is safe too, but it blocks folate absorption. That’s why you need a daily 1 mg folic acid supplement. Don’t rely on prenatal vitamins alone-most only have 0.4 mg. Ask for a prescription-strength version.
Biologics: Anti-TNFs, Vedolizumab, and Ustekinumab
If you’re on a biologic, you’re probably worried. But here’s what the data says:
Anti-TNFs like infliximab (Remicade) and adalimumab (Humira) have the most safety data of any IBD drug in pregnancy. Over 2,000 pregnancies in the PIANO registry show no increase in birth defects, preterm birth, or miscarriage. The rate of congenital anomalies? 2.6%-almost identical to the general population (2.8%).
One twist: these drugs cross the placenta, especially in the third trimester. That means your baby could have drug levels in their blood at birth. For that reason, many doctors stop dosing after week 30. It’s not because the drug is dangerous-it’s to reduce the chance of your newborn having a suppressed immune system in the first few months. Your baby can still get all their vaccines on schedule. No need to delay.
Vedolizumab (Entyvio) is newer, but data from the CONCEIVE study and over 100 pregnancies show no increase in birth defects or serious infections. One early study showed lower live birth rates, but that was because many women were still having active disease. When disease was controlled, birth outcomes matched the general population. If you’re on vedolizumab, keep it going.
Ustekinumab (Stelara) has data from nearly 700 pregnancies. A 2024 European study of 78 babies exposed in utero found no increase in preterm birth, low birth weight, or malformations-even when moms got induction doses early in pregnancy. The FDA and ECCO both consider it safe. You don’t need to stop.
What to Avoid at All Costs
There are two drugs you must stop before conception-and never restart during pregnancy:
- Methotrexate: A known teratogen. Even a single dose can cause severe birth defects like missing limbs, facial clefts, and brain malformations. Risk? Up to 27%.
- Thalidomide: Infamous for causing phocomelia (flipper-like limbs). Still used in rare cases for IBD, but absolutely forbidden in pregnancy.
Both are Category X-meaning the risks are proven and unacceptable. If you’re on either, use two forms of birth control. Talk to your doctor about switching to a safer option at least 3 months before trying to conceive.
JAK Inhibitors: Tofacitinib and Upadacitinib
These newer oral drugs-like tofacitinib (Xeljanz)-are convenient, but pregnancy data is thin. A small study of 11 pregnancies showed no red flags. But here’s the problem: JAK inhibitors interfere with a pathway (JAK-STAT) that’s critical for early embryo development. Animal studies show fetal loss and malformations.
Because of this, the Crohn’s & Colitis Foundation recommends stopping tofacitinib at least 1 week before conception. For upadacitinib, the ECCO guidelines suggest stopping 4-6 weeks before trying. It’s a precaution, not a panic. But if you’re planning pregnancy, switch to an anti-TNF or vedolizumab instead.
Immunomodulators: Azathioprine and 6-MP
These older drugs-azathioprine and mercaptopurine (6-MP)-have been used in pregnancy for decades. The PIANO registry shows no increase in birth defects. In fact, they’re often the bridge for women who can’t tolerate biologics.
Keep taking them. Monitor your blood counts every 4-6 weeks. Low white blood cell counts can increase infection risk, so your doctor will check regularly. Don’t stop unless your counts drop dangerously low. The risk of a flare from stopping outweighs the tiny risk from the drug.
Corticosteroids: Use Sparingly
Prednisone and budesonide are great for flares-but not for long-term use in pregnancy. Taking steroids in the first trimester slightly increases the risk of cleft lip or palate (1.4-2.3 times higher). That’s still a small absolute risk, but why take it if you don’t have to?
Use steroids only for acute flares, and get off them as soon as possible. Your goal is steroid-free remission before conception. If you’re still on steroids when you get pregnant, your team needs to act fast to get you on a safer maintenance drug.
What About Breastfeeding?
Yes, you can breastfeed while on most IBD meds.
Anti-TNFs, vedolizumab, ustekinumab, azathioprine, and mesalamine all pass into breast milk in tiny amounts-far below levels that would affect your baby. The AAP and ECCO both say it’s safe.
Sulfasalazine? A little more complicated. It breaks down into sulfa and mesalamine. Sulfa can rarely cause jaundice in newborns with G6PD deficiency. It’s rare, but if your baby is at risk, your doctor might suggest switching to mesalamine alone. Otherwise, go ahead and nurse.
Never breastfeed if you’re on methotrexate or thalidomide. Ever.
Planning Ahead: The 3-Month Rule
The best time to adjust your meds isn’t when you’re pregnant. It’s before you conceive.
Experts recommend achieving clinical and endoscopic remission-meaning no symptoms and no inflammation visible on colonoscopy-for at least 3 months before trying. That’s your sweet spot. You’re not just protecting your baby-you’re protecting yourself from complications like preterm labor, preeclampsia, and cesarean delivery.
Work with both your gastroenterologist and OB-GYN. Don’t let them argue over who’s in charge. You need a team. Your IBD doctor handles meds. Your OB handles pregnancy. Together, they make sure you’re not caught in the middle.
And if you’re anxious? You’re not alone. A 2022 survey found 68% of pregnant IBD patients were terrified of their meds harming the baby. But here’s the flip side: 42% of community gastroenterologists couldn’t name all the safe drugs. That’s not your fault. It’s a system problem. Arm yourself with the facts. Bring the PIANO guidelines to your appointment. Ask: Is this drug on the safe list?
What’s New in 2025?
The science is moving fast. In 2024, the FDA approved mirikizumab for IBD-with a mandatory pregnancy registry. The first randomized trial comparing vedolizumab vs. anti-TNF in pregnancy (NCT04102616) is wrapping up results. And researchers are building tools to predict how much of your drug crosses the placenta-so you can tailor dosing like never before.
By 2025, a shared decision-making tool will be available to help you and your doctor weigh risks and benefits in real time. No more guessing. No more fear.
The message hasn’t changed: Your health matters as much as your baby’s. Staying on the right medication doesn’t make you a risk-it makes you a responsible parent. Uncontrolled IBD is the enemy. Your meds? They’re your shield.
Can I get pregnant if I have IBD?
Yes, absolutely. Most women with IBD have healthy pregnancies and babies. The key is being in remission before conception. If your disease is active, your risk of complications goes up-but that’s not because of your meds. It’s because of the inflammation. Get your IBD under control first, then try to conceive.
Will my baby inherit IBD?
There’s a slightly higher chance-if one parent has IBD, the child has about a 5% risk of developing it. If both parents have it, that jumps to 30%. But it’s not guaranteed. Genetics play a role, but environment, diet, and gut microbiome matter too. There’s no way to prevent it, but knowing the risk helps you monitor your child’s health early.
Should I stop my meds if I get sick during pregnancy?
No. If you develop a flare, stopping your meds will make it worse. The goal is to keep your disease quiet. If you need a short course of steroids for a flare, that’s okay-but work with your doctor to get back on your regular, safe maintenance drug as soon as possible. Don’t let fear of meds lead to a flare that puts you and your baby at risk.
Is it safe to have a colonoscopy while pregnant?
Yes, if it’s medically necessary. Colonoscopies are safe during pregnancy, especially in the second trimester. Sedation is adjusted to protect the baby. If you’re having symptoms like bleeding, pain, or weight loss, your doctor may recommend one to check if your IBD is active. Not doing it could mean missing a flare that needs treatment.
Can I breastfeed if I’m on biologics?
Yes. Drugs like infliximab, adalimumab, vedolizumab, and ustekinumab don’t pass into breast milk in significant amounts. Even if they do, they’re proteins that get broken down in the baby’s gut-they won’t enter the bloodstream. The American Academy of Pediatrics and ECCO both say breastfeeding is safe and encouraged. Don’t stop nursing because you’re on these meds.
What if I get pregnant unexpectedly while on methotrexate?
Stop methotrexate immediately and contact your doctor right away. Don’t panic. The risk of birth defects is highest in the first 8 weeks, but early intervention helps. You’ll need a detailed ultrasound and possibly a fetal echocardiogram. Most women who stop methotrexate early and switch to safe meds go on to have healthy babies. The key is acting fast.
Do I need to change my diet during pregnancy with IBD?
Focus on balanced nutrition-not extreme diets. Pregnancy increases your need for iron, folate, calcium, and protein. If you have active IBD, you may need supplements. Avoid raw fish, unpasteurized cheese, and undercooked meat. If you’re on a low-FODMAP or specific carbohydrate diet, keep it-but make sure you’re getting enough calories and nutrients. Talk to a dietitian who understands both IBD and pregnancy.
Can I have a vaginal delivery with IBD?
Yes, unless you have active perianal disease (fistulas or abscesses) or a history of rectal surgery. Most women with IBD can deliver vaginally. A C-section isn’t automatically needed. Your OB will decide based on your individual situation-not just your IBD diagnosis. If you’re in remission, your delivery should be no different from any other low-risk pregnancy.
Written by Felix Greendale
View all posts by: Felix Greendale