Amyotrophic Lateral Sclerosis during pregnancy an uncommon association

Background: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that shows a combination of upper and lower motor neurons signs and symptoms. The association of ALS and pregnancy has low prevalence due to demographic characteristics of the disease. Case: A 29-year-old woman, healthy, who comes to the clinic at week 29 of gestation, manifests progressive weakness, distal hypotrophy, and dysphagia. On examination signs of upper and lower motor neuron with involvement in cervical, bulbar, thoracic and lumbar segments. The pregnancy developed without complications; adequate prenatal control, and cesarean section as resolution of pregnancy. Conclusion: Pregnancy may be associated with the development of latent ALS due to hormonal factors related to the increase of progestogens, which would decrease the neuroprotective effect of estrogens, being the trigger of the disease. Vaginal delivery is facilitated, but respiratory compromise would determine the cesarean delivery.