Outcome of pregnancies after onset of the neuromyelitis optica spectrum disorder

Background and purpose: Data on the pregnancy outcome of neuromyelitis optica spectrum disorder (NMOSD) remain limited, especially for woman who had received immunosuppressive treatment before becoming pregnant. The aim was to evaluate the outcome of pregnancy amongst patients with NMOSD who attempted to become pregnant after NMOSD onset and to identify risk factors that predict pregnancy-related attack.

Methods: Medical records from 29 patients who attempted to become pregnant after NMOSD onset were retrospectively evaluated and the patients were interviewed for pregnancy outcomes. Pregnancy-related attack was defined as an attack that occurred during pregnancy or within 1 year of delivery.

Results: Amongst the 29 patients, 26 had 33 pregnancies after NMOSD symptom onset. The 33 pregnancies after NMOSD onset resulted in 24 live births (healthy neonates except one with low birth weight), six miscarriages and three elective abortions. Pregnancy-related attack occurred in nine (75%) of 12 pregnancies before initiation of immunosuppressive therapy, but in only five (24%) of 21 pregnancies after initiation of immunosuppressive therapy (P = 0.009). Multivariable analysis indicated that pregnancy-related attack was negatively associated with pregnancy after initiation of rituximab (odds ratio 0.048, 95% confidence interval 0.004-0.546).

Conclusion: Successful pregnancy without maternal and neonatal complications may be feasible in patients with NMOSD. Rituximab treatment before pregnancy might help to prevent pregnancy-related attack in patients with NMOSD.