Myasthenia gravis (MG) is an autoimmune disorder characterized by muscle weakness caused by impaired function of the acetylcholine (ACh) receptors at the neuromuscular junction.

How does mysasthenia gravis affect pregnancy?

many studies show that MG does not have a severe adverse effect on pregnancy, without increased risk of miscarriage or premature births. Infants born to mothers with MG can develop transient neonatal MG. in about 10% to 20% of cases likely due to  placental transfer of immunoglobulin G antibodies in the second and third trimesters.Transient neonatal MG usually reverses itself after 3 weeks  without complication.

How does pregnancy affect mysasthenia gravis?

It is normal to see MG in pregnancy and the effect of pregnancy on MG varies considerably among women and even between pregnancies in the same woman.  In general, 1/3 of symptoms stay the same, 1/3 get worse and 1/3 get better

Late pregnancy can have an immunosuppressive effect leading to often to improved symptoms Worsening of symptoms are more likely in the first trimester or postpartum after delivery. General recommendations are that after onset of MG women delay pregnancy for at least 2 years.

Delivery is usually not affected by MG and cesarean section should only be done for usual indications.