Pregnancy in Seronegative Myasthenia Gravis: A Single-Center Case Series.

INTRODUCTION: The course of double-seronegative myasthenia gravis (DSNMG) during and after pregnancy has not been well described.

OBJECTIVE: To assess the course of DSNMG during pregnancy and within 6 months postpartum.

METHODS: A retrospective cohort study of women with DSNMG seen in the Duke Myasthenia gravis (MG) Clinic after 2003.

RESULTS: Review of the Duke MG Clinic Registry and electronic medical record identified 8 patients who became pregnant after MG onset; the mean age at disease onset was 17.6 (SD = 10.0) years. Increased MG symptoms were observed in the first and third trimester and, most commonly, postpartum in 6 of 18 pregnancies. Except for 1 infant who developed respiratory distress that required neonatal intensive care admission, all the newborns were healthy at birth.

CONCLUSIONS: As in seropositive MG, increased MG symptoms during pregnancy and within 6 months postpartum is also seen in women with DSNMG.