Multiple Sclerosis in Pregnancy

Multiple sclerosis in pregnancy is an immune mediated demyelinating disease of the central nervous system in a pregnant woman. It affects young women, and pregnancy lowers the relapse rate in the third trimester, while relapses rise in the first 3 months after delivery. It matters because several disease modifying drugs are harmful in pregnancy.

• Pregnancy does not worsen long term disability.
• Breastfeeding and relapse risk: exclusive breastfeeding may lower relapse.
• Disease modifying treatment decisions should be made before conception.

Women have visual loss, numbness, weakness, imbalance, bladder symptoms, fatigue and spasticity, with relapses lasting days to weeks. Examine vision, strength, reflexes, sensation and gait.

• Optic neuritis and sensory symptoms are common first signs.
• Fatigue worsens with heat.
• Differential diagnosis: transverse myelitis, neuromyelitis optica, stroke, vitamin B12 deficiency, HIV, syphilis, neurocysticercosis, compression of the cord.
• Complications: relapse, urinary tract infection, pressure sores, depression, postpartum relapse, disability progression.

The diagnosis is usually known; new symptoms need relapse confirmation.

• Clinical review for new or worsening symptoms lasting more than 24 hours in the absence of fever.
• MRI of the brain and spine without gadolinium to confirm new lesions.
• Urine culture, full blood count, glucose and electrolytes to exclude infection and other causes of worsening.
• Vitamin D level where available.

The principle is to stop harmful drugs, treat only disabling relapses and plan for the postpartum period.

• Supportive: physiotherapy; avoid overheating; treat infection early; pelvic floor exercises; vaginal delivery is normal; epidural anaesthesia is allowed; exclusive breastfeeding.
• Pharmacological: for a disabling relapse give methylprednisolone 1 g IV daily for 3 to 5 days, avoiding the first trimester where possible; baclofen 5 mg oral 8-hourly increased to 10 to 20 mg 8-hourly (maximum 80 mg daily) for spasticity, with slow withdrawal only; oxybutynin 5 mg oral 8-hourly for bladder urgency; vitamin D 1000 to 2000 IU oral daily; folic acid 400 micrograms oral daily; stop teriflunomide before conception and give cholestyramine 8 g oral 8-hourly for 11 days to speed elimination; stop fingolimod 2 months and siponimod 10 days before conception; avoid pregnancy for 6 months after the last dose of cladribine and for 12 months after the last dose of ocrelizumab; glatiramer and interferon beta can continue where unavoidable.
• Procedures: none.
• Special groups: women with severe disability need planned delivery with physiotherapy and bladder care; the newborn of a woman who received ocrelizumab or natalizumab needs blood count and infection review.
• Red flags: new weakness, visual loss, urinary retention, severe headache, fever with worsening symptoms, bulbar weakness.
• Follow-up: neurology review each trimester and at 6 weeks, 3 months and 6 months postpartum; restart disease modifying treatment soon after delivery if not breastfeeding or per specialist advice.