Introduction
A woman's physiology changes dramatically during pregnancy. Pregnant women typically experience immunocompromised conditions, as their immune systems become less reactive to allow the baby to grow safely. Pregnancy presents unique difficulties for anyone with an inflammatory disease of any kind, such as neuromyelitis optica spectrum disorder (NMO). Numerous studies have examined how neuromyelitis optica spectrum disorder (NMOSD) affects conception and pregnancy. Antibodies against aquaporin-4 (AQP4) cause NMOSD. Research shows that AQP4 can influence hormone levels by disrupting the hypothalamic-pituitary-gonadal axis and causing aberrant endometrial thickness, which can result in infertility.
What Is NMOSD?
Neuromyelitis optica spectrum disorder (NMOSD), often called neuromyelitis optica (NMO), Devic disease, or optic neuritis, is an uncommon inflammatory disease that primarily affects the spinal cord (myelitis) and optic nerves (optic neuritis). However, it can also happen in the brain. The autoimmune illness NMOSD causes demyelination. This indicates that the body's immune system attacks the myelin, or protective sheath, surrounding nerves. This condition could develop following an infection. Alternatively, it can be connected to another autoimmune disease.
Neuromyelitis optica can cause symptoms like painful spasms, weakness or paralysis in the arms or legs, and blindness in one or both eyes. Additionally, spinal cord damage may result in a lack of feeling, uncontrollable vomiting, hiccups, and issues with the bladder or bowel.
Neuromyelitis optica resembles multiple sclerosis (MS) in its symptoms and was formerly thought to be a variation of MS. Compared to MS, neuromyelitis optica spectrum illness carries a higher chance of disability. Relapses happen frequently. One of the most important ways to avoid disability is to stop recurring attacks. While flare-ups of neuromyelitis optica may be curable, they might cause persistent sight loss and difficulty walking.
How Does Neuromyelitis Optica Spectrum Disorder Affect Pregnancy?
The connection between pregnancy and NMOSD is not well studied. However, some research suggests that individuals with NMOSD may be more likely to experience pregnancy-related problems. Women with NMOSD may experience more obstetric complications for several reasons. AQP4-IgG antibodies can bind to AQP4 proteins on placental cells and go through the placenta. While some research implies that AQP4 expression peaks in mid-pregnancy, which may be the most significant risk period for complications, others demonstrate that it declines from the first to the third trimester. In one study, pregnant mice were injected with human AQP4-IgG and complement, which resulted in neutrophil infiltration, inflammation of the placenta, and death of the fetus. Complement and AQP4-IgG were necessary for this inflammation; the other would not have occurred without one. Stillbirth, intrauterine growth restriction, and hypertension can all result from placental malfunction. In addition to the typical symptoms of pregnancy and the possible negative consequences, NMOSD can present particular difficulties, which include:
Infertility:
It is unclear how NMOSD affects fertility. Women with NMOSD are frequently older, and an important contributor to decreased fertility due to inferior egg quality and quantity is higher maternal age. AQP4 is a protein found in the hypothalamus. The gonadotropin-releasing hormone (GnRH), which regulates the release of sex hormones, is produced by the hypothalamus. As a result, in NMOSD patients, AQP4 antibodies may have an impact on hormone levels and fertility. In one study, 217 NMOSD patients' pregnancy histories were examined by Bove et al. It was discovered that six percent required fertility treatment, and 13 percent had over a 12-month wait to become pregnant.
Miscarriages and Fetal Death:
Patients with NMOSD may have pregnancy loss at any point during the gestational cycle. Studies' findings show that many pregnancies end in losses before they reach viability, such as spontaneous miscarriages and abortions brought on by the illness or its treatment. While there is a scarcity of data related to trimesters, most reported losses happen in the first trimester.
Additionally, there is a correlation between the time interval between fetal loss and the mother's deteriorating health. Miscarriages followed transverse myelitis episodes that required plasma exchange, and large doses of steroids were noted.
There have also been reports of stillbirths occurring when a mother experiences seizures while pregnant. These results highlight the necessity of closely monitoring and treating NMOSD during pregnancy to reduce hazards.
Preeclampsia:
The risk of preeclampsia (high blood pressure that can occur during pregnancy) is higher in patients with NMOSD and other autoimmune conditions. However, a recent study in NMOSD patients shows lower risks than previously thought, similar to or lower than those in the general population.
Relapses in NMOSD Patients:
The annualized relapse rate (ARR), which counts the number of relapses per patient annually, is frequently used to quantify relapses in NMOSD patients. This measurement is utilized during pregnancy and postpartum to understand relapse trends. Research shows that during and immediately after pregnancy, there is an increased chance of relapse and more disability, particularly for women who were not receiving immunosuppressive treatment at the time of conception.
How Is Neuromyelitis Optica Spectrum Disorder Managed During Pregnancy?
Preconception Counseling:
Women with NMOSD who are considering becoming pregnant must receive preconception counseling. NMOSD is not known to have an impact on fertility. Preconception counseling includes discussing the possible dangers and difficulties of pregnancy, such as how NMOSD affects fertility and pregnancy outcomes and whether or not drugs are safe to take while pregnant.
Medication Management Before Conception:
Mycophenolate mofetil, Azathioprine, and Rituximab are just a few of the many drugs used to treat NMOSD that need to be carefully monitored during pregnancy due to their potential teratogenic consequences. Certain medications, such as Methotrexate, Mitoxantrone, and Mycophenolate mofetil, must be discontinued before conception, so the NMO treatment may need to be adjusted several months before becoming pregnant. The safety profile for the growing fetus and the medication's effectiveness in managing NMOSD must be taken into account.
Medication Management During Conception:
Based on the medical history, doctors will carefully determine which NMO medications are safe to take while pregnant. Even so, medication changes may be customized for patients while pregnant, depending on how well the NMO is managed. Attacks are more likely to occur during pregnancy. Therefore, even if the current treatment plan is safe, it might not be as effective when an individual is pregnant.
Delivery and After-Care:
To plan for probable problems, a comprehensive discussion with the obstetric team should be part of delivery planning. Obstetric indications should guide the method of delivery, not just NMOSD. Severe neurological impairment, however, can affect the choice. Because there is a higher chance of NMOSD relapses following birth, postpartum care is essential. To guarantee the well-being of the mother and the newborn, ongoing monitoring and suitable treatment modifications are required.
Conclusion
Women with NMOSD experience particular difficulties when they approach childbearing age. Preeclampsia and miscarriages are among the obstetric problems linked to pregnancy in patients with NMOSD. Pregnancy may raise the mother's risk of relapse, and the postpartum period significantly increases that risk as well. Due to the disease's potential to affect both fertility and pregnancy outcomes, cautious management and vigilant observation are required. Optimizing outcomes for mother and child requires preconception counseling, appropriate medication modifications, and a multidisciplinary approach to care.
