Pregnancy and Autoimmune Disease: Medication Safety and Planning

Planning a pregnancy when you have an autoimmune disease isn’t about choosing between being healthy or having a baby-it’s about doing both safely. For women with conditions like lupus, rheumatoid arthritis, or psoriatic arthritis, the fear of flares or birth defects often leads to stopping meds too early-or not stopping them when they should. But the latest evidence shows that medication safety during pregnancy has changed dramatically. Most treatments aren’t the threat they used to be. In fact, uncontrolled disease is often far riskier than the drugs themselves.

What Medications Are Safe During Pregnancy?

Not all autoimmune drugs are created equal. Some are safe to keep taking, others need to be switched months before conception, and a few must be stopped completely. The key is knowing which is which.

Hydroxychloroquine, commonly used for lupus and rheumatoid arthritis, is one of the safest options. Studies tracking over 12,450 pregnancies show no increase in birth defects. It actually reduces the chance of a flare by two-thirds and cuts the risk of preterm birth and preeclampsia in half. If you’re on this drug, keep taking it.

Azathioprine and sulfasalazine also have strong safety records. Azathioprine has been used in more than 5,800 pregnancies with only a 2.1% risk of preterm birth-far lower than the 8.7% risk when lupus or RA is active. Sulfasalazine shows no signs of harming the baby, even at high doses.

TNF inhibitors like adalimumab, etanercept, and infliximab are generally safe too. Over 28,740 documented pregnancies show no major increase in birth defects. But there’s a catch: not all TNF blockers behave the same. Certolizumab pegol stands out because it barely crosses the placenta-only 0.2% of the mother’s level reaches the baby. That’s why it’s often the top choice for women in their third trimester. Adalimumab and infliximab cross more easily, so some doctors recommend stopping them after 30 weeks to reduce newborn exposure.

What Medications Should Be Avoided?

Some drugs are absolute no-gos during pregnancy. Methotrexate is one of them. It’s a powerful immune suppressor, but it’s also a known teratogen. Studies from the OTIS registry show that 17.8% of babies exposed to methotrexate in early pregnancy have major birth defects-like missing limbs, cleft palate, or heart problems. You need to stop it at least three months before trying to conceive.

Mycophenolate mofetil is even riskier. The FDA has a black box warning for it. In over 300 documented cases, 24.4% of babies had serious abnormalities-missing ears, eye defects, cleft lip. You must switch away from this drug at least six weeks before conception, but many doctors recommend a full three-month buffer.

JAK inhibitors like tofacitinib and upadacitinib are still being studied. EULAR and the FDA advise avoiding them entirely during pregnancy due to theoretical risks. But Japan’s data is surprising: in 47 pregnancies where upadacitinib was continued through the first trimester, only 1.8% of babies had birth defects-lower than the national average. This gap in evidence means decisions here should be made carefully with your rheumatologist.

When Should You Start Planning?

Waiting until you miss a period is too late. The ideal time to talk about meds and pregnancy is at least six months before you plan to conceive. That gives your body time to adjust.

Many women stop their meds because their OB says it’s safer. But outdated advice still lingers. One patient stopped adalimumab at eight weeks because her OB warned of “too much exposure.” She ended up with a severe flare at 20 weeks, needed high-dose prednisone, developed gestational diabetes, and delivered at 34 weeks. Another woman stayed on hydroxychloroquine and certolizumab throughout-her baby was born at 39 weeks, healthy and full-term.

Switching meds takes time. Methotrexate needs three months to clear. Mycophenolate needs six weeks. Even if you’re not trying to get pregnant right now, if you’re in your reproductive years, it’s worth reviewing your meds now. Your rheumatologist should be part of your care team, not just a specialist you see when you’re flaring.

What About Breastfeeding?

Breastfeeding is safe with almost all autoimmune medications. Biologics like adalimumab, infliximab, and certolizumab are so large that they don’t pass into breastmilk in meaningful amounts. Studies show adalimumab levels in breastmilk are 0.005% to 0.13% of the mother’s blood concentration-far below any level that could affect the baby.

Hydroxychloroquine, azathioprine, and sulfasalazine are also considered safe during breastfeeding. The American Academy of Pediatrics lists all of them as compatible with nursing. There’s no need to pump and dump. In fact, continuing your medication while breastfeeding helps prevent postpartum flares-which are common and can be severe.

Why Do So Many Women Stop Medication Without Talking to a Doctor?

A registry of over 12,800 women found that 41.7% stopped their autoimmune meds on their own because they were scared. Reddit threads are full of stories: “My OB told me to stop everything at 12 weeks,” or “I didn’t know certolizumab was safe.” Many doctors still rely on old guidelines from 2010 or earlier.

But the data is clear: women who get preconception counseling from both a rheumatologist and a maternal-fetal medicine specialist have 53% fewer unplanned medication changes and 37% higher rates of full-term births. That’s not a small difference-it’s life-changing.

What’s Changing in 2025 and Beyond?

The field is moving fast. In January 2024, the American Board of Medical Specialties officially recognized Maternal-Fetal Medicine sub-specialization in Rheumatology. That means more clinics are opening, more specialists are trained, and more women will get coordinated care.

The NIH launched a $12.7 million research network in early 2024 to study newer drugs like JAK inhibitors in pregnancy. EULAR is releasing a patient decision tool in November 2024 to help women weigh risks and benefits. ACOG is updating its guidelines in Q2 2025 to match the latest EULAR data.

And there’s good news on the drug front. Eight biosimilars of adalimumab entered the market after its patent expired in January 2023. They’re cheaper, but they’re just as safe during pregnancy as the original. No need to worry about switching to a biosimilar-it’s the same medicine.

What Should You Do Now?

If you’re thinking about pregnancy, here’s your checklist:

• Review every medication you’re taking with your rheumatologist-not your OB, not your pharmacist, not Google.
• Ask: “Is this safe before, during, and after pregnancy?”
• If you’re on methotrexate or mycophenolate, ask when to switch and what to switch to.
• If you’re on a TNF inhibitor, ask whether certolizumab is an option for you.
• Request a joint appointment with a maternal-fetal medicine specialist if your clinic offers it.
• Keep taking hydroxychloroquine if you’re on it. It’s one of the best pregnancy protectors we have.

There’s no such thing as a risk-free pregnancy. But with the right plan, the risks are manageable. You don’t have to choose between your health and your baby. You can have both.