Congenital Myasthenic Syndrome in Pregnancy: A Case Report and Literature Review on Peripartum Management Strategy

Congenital myasthenic syndromes (CMS) are a group of rare inherited neuromuscular disorders caused by defects in neuromuscular transmission. Unlike autoimmune myasthenia gravis, CMS typically presents in childhood with variable severity and symptoms, and does not involve autoantibodies. This report presents the management of a primigravida diagnosed with CMS who was generally stable on pyridostigmine therapy but experienced a severe exacerbation during pregnancy. The diagnosis of CMS was made on clinical grounds, but the genetic testing for confirmation of the exact mutation was not available. The patient experienced intermittent mild exacerbations before pregnancy, managed with short courses of prednisolone. A severe exacerbation at 20 weeks of gestation required intensive care unit admission for respiratory support. Despite plans for a vaginal delivery, she developed exhaustion and desaturation during labour, followed by foetal distress, necessitating emergency caesarean section. Postpartum, the patient returned to her baseline functional status, and the neonate showed no signs of neuromuscular weakness. This case highlights that pregnancy in women with CMS can be safely managed with careful monitoring, multidisciplinary planning, and readiness to escalate care when needed. Delivery plans should be flexible, and management should be tailored to the individual's clinical course. Since the neonatal outcome is unpredictable in the absence of genetic testing, follow-up care is necessary in all cases.