BACKGROUND:

Hyperemesis gravidarum is a serious condition that can affect up to 2% of pregnant women. This condition can lead to Wernicke's encephalopathy due to a deficiency in vitamin B1 which, in its active form, plays a decisive role in neuronal metabolism.

OBJETIVE:

To contribute to the understanding of preventive aspects and diagnosis and to insist on the importance of early treatment to reduce morbidity and maternal and perinatal mortality derived from this condition.

CLINICAL CASE:

Patient 18 weeks pregnant who in the context of hyperemesis gravidarum resulted in Wernicke's encephalopathy complicated by severe fetal hydrocephalus.

CONCLUSIONS:

This neurological emergency is characterized by a classic triad: ataxia, confusion and ophthalmoplegia that does not always manifest in its entirety, making diagnosis difficult. If diagnosis and treatment are not established early, irreversible complications may arise.