NMO and Pregnancy
Last updated: April 2023
Pregnancy strains the body. When you are pregnant, your immune system becomes less reactive so your baby can grow safely. For this reason, doctors call pregnancy an immunocompromised state. Having any sort of autoimmune disease, such as neuromyelitis optica spectrum disorder (NMO), during pregnancy creates additional challenges.
How can NMO affect your pregnancy?
NMO causes the immune system to attack the central nervous system (brain, spine, and nerves of the eye). This can cause episodes of vision loss, paralysis, or loss of sensation. Spinal cord damage caused by NMO can also cause vomiting or problems with the bladder and bowels.
Because many NMO drugs cannot be taken during pregnancy, NMO can be especially tough to manage while you are pregnant.1-2
NMO statistics: Diagnosis during pregnancy
NMO is up to 9 times more likely to affect women than men. The average age of onset is around 30 to 40 years old. Since many people have children in their 30s, many are diagnosed with NMO during their childbearing years. Here, we describe what to expect when you’re expecting and have NMO.3
How can NMO affect my pregnancy?
In many people with NMO, the immune system sends out chemicals called antibodies to attack a protein called aquaporin-4 (AQP4). AQP4 is found on cells in the brain called astrocytes. When the antibodies attack AQP4, they kill the astrocytes.
This causes inflammation of the nervous system and NMO symptoms.3-4 AQP4 is also found on placenta cells, meaning antibodies can attack the placenta and cause harm to the baby.
This contributes to the following issues for pregnant people with NMO:3-4
- Intrauterine (in the womb) growth restriction
- Raised risk of miscarriage
- Poor pregnancy outcomes
- High-risk pregnancy
MOG NMO and pregnancy
Some people with NMO do not have AQP4-mediated NMO. Instead, they make antibodies to a protein called myelin oligodendrocyte glycoprotein (MOG). MOG-mediated NMO is different and more research is needed to understand it. The same is true for people with NMO who are seronegative (do not make antibodies to AQP4 or MOG). Because of these differences, the information below is for those with NMO and AQP4 antibodies.5
What should I do about my NMO if I am pregnant or want to be?
NMO must be managed before, during, and after pregnancy.
Managing NMO before conception
Your NMO treatment may need to change several months before you want to get pregnant. Many drugs must be stopped before conception, including:4
- Mycophenolate mofetil
You also may need to time your last dose of some drugs close to conception time. If you take rituximab or ocrelizumab, you must take another course if you have not conceived within 6 months.4
Doctors will carefully assess which NMO drugs are safe based on your health history. Even then, drugs may be adjusted during pregnancy based on how they manage your NMO. There is a higher risk of attacks during pregnancy. So even if your usual treatment regimen is safe, it may not work as well during pregnancy.4,6
Some NMO treatments include corticosteroids. Using steroids during pregnancy has few complications, but has been linked to low birthweights and smaller head sizes.3
Delivering your baby
Because pregnancy when you have NMO carries a higher risk, it is recommended that you give birth in a hospital. Women with NMO have a higher risk of deep vein thrombosis, so doctors will monitor and treat this during pregnancy and delivery. You can give birth either vaginally or by cesarean section. Neither way of delivering is better or worse when it comes to the risk of relapse.3
NMO treatment after giving birth
After delivery, your treatment may differ depending on if you choose to breastfeed. If you are not breastfeeding, treatment can be restarted shortly after delivery. If you are breastfeeding, your doctor will discuss which drugs may be safest for you and your baby. If you breastfeed and have bad NMO symptoms, your doctor may try to start you on azathioprine or monoclonal antibodies. They may also consider:4
- Plasma exchange
- Immunoadsorption (removal of certain antibodies)
People with NMO have a high risk of relapse during the postpartum period. No matter how you choose to feed your baby, your doctor will likely want to restart your NMO treatment as soon as possible.6
How will NMO affect my baby?
AQP4 antibodies pass from mother to baby. They can be found in the blood of newborns for up to 3 months, but none of the babies in a 2012 study showed clinical symptoms of NMO. Doctors will likely monitor your baby to make sure all is well.3-4
Prepare, and talk to your doctor
There are many people with NMO who have successful, safe pregnancies and healthy babies. The best outcomes are seen with those who talk to their obstetrician and neurologist before conceiving so that a good treatment plan can be put into place.
Did you experience pregnancy and NMO at the same time? What was that like? Share with us in the comments.
Typically, how much time passes between attacks for you?