What is transient neonatal Myasthenia Grevis?
Approximately 12% of neonates born to mothers with Myasthenia Grevis are “floppy” babies who have difficulty with breathing and sucking.
This “transient neonatal myasthenia” likely results from the transfer of maternal AChR antibodies to the infant through the placenta.
It typically lasts for several weeks and then spontaneously resolves but should not persist for more than 12 weeks.
Neither the severity of maternal disease nor the titers of maternal antibody reliably correlate with the development of neonatal Myasthenia Grevis.
Severely affected mothers may have normal infants, and mothers in clinical remission may have affected infants.
Regardless, physicians caring for a myasthenic mother must be aware of this disorder and must be prepared to provide respiratory support to the newborn, if needed.
