What to do when a woman conceives taking a teratogenic medication
Take a deep breath. Be empathetic – this is a really scary and emotional time for the patient.
Check the medications:
- Stop the medications on the STOP & CAUTION list.
- Continue the medications on the GO list.
- Start a prenatal multivitamin
- If pregnant on methotrexate: start folic acid 5mg a day.
- If pregnant on leflunomide: start cholestyramine washout of 8 g 3 times daily for 11 days.
Estimate exposure:
- When was her last menstrual period? (conception is estimated to be 2 weeks later)
- When did she take teratogenic medications? Many women struggle to this answer this clearly.
Assess lupus activity:
- The usual lupus laboratory tests (urinalysis, urine protein:creatinine ratio, dsDNA, complement, CBC, etc.).
- Current signs and symptoms of inflammatory lupus.
- Determine lupus activity over the prior 6 months based on her history and use of prednisone or other medications.
Maintain control (or gain control) of lupus activity:
- Continue hydroxychloroquine.
- If she was on mycophenolate, cyclophosphamide, or methotrexate, strongly consider adding azathioprine (or cyclosporine or tacrolimus as 2nd choice) to avoid a lupus flare in pregnancy.
- Treat with azathioprine with or without tacrolimus plus moderate to high doses of prednisone if lupus is currently active, especially with lupus nephritis.
Need help?
- Call an obstetrician. They will likely want to do an ultrasound to confirm viability and date the pregnancy.
- MotherToBaby can talk with you or the patient to help describe risks and options. (MotherToBaby.org)
Help the woman decide what to do next:
- What is her general feeling about the pregnancy? Some states in the U.S. currently restrict access to termination services. We recommend knowing in advance what the options and restrictions are for where you are practicing.
- Explain in simple terms and numbers to explain the risks to her and her fetus due to her lupus activity and exposure to teratogens (see statistics below).
- The ultimate decision is up to her. Make it clear that you care about her and will do your very best to be supportive of her choice.
Statistics
| Pregnancy Loss Estimated risk with 1st trimester drug exposure | Birth Defect Estimated risk with 1st trimester drug exposure | |
| Healthy normal pregnancy | ~15% | ~3% |
| A woman with lupus (not on a STOP List medication) | ~25% | ~3% |
| Hydroxychloroquine | No increase risk | No increase risk |
| Azathioprine | No increase risk | No increase risk |
| The STOP List Medications: | ||
| Methotrexate | ~40% | ~7% |
| Mycophenolate mofetil (Cellcept®) & Mycophenolic Acid (Myfortic®) | ~40% | ~25% |
| Cyclophosphamide (Cytoxan®) | ~50% | ~25% |
| Thalidomide & Lenalidomide (Revlimid®) | Increased, but unknown how common | ~20% |
| Leflunomide (Arava®) | No increase after cholestyramine washout | No increase after cholestyramine washout |
Practice Suggestion
Print the STOP and GO Lists for your nursing team so they can quickly answer questions for anxious patients. Having the nurse tell a patient to stop a needed and compatible medication will make it much harder for you to convince her to take it during pregnancy. Delays in stopping teratogens can put the pregnancy at higher risk than necessary
Last Updated 11/2023
