We describe the first case of pregnancy in a patient with amyotrophic lateral sclerosis (ALS) reported in Uruguay. The 27-year-old white woman who came to our clinic complaining of general weakness and gait symptoms was diagnosed as being pregnant and met the El Escorial criteria of probable ALS. The advised abortion caused her to abandon medical treatment, which was only resumed after a period of severe deterioration, at 32 weeks of gestation. After several days of serious vital risk, as evaluated by a multidisciplinary team, a normal male baby was born. Four months later, the patient had gradually improved and reached a stable condition, but presented with restrictive ventilatory distress.