RESUMO
A 33-year-old woman in her first pregnancy with no significant medical history had a tonic-clonic seizure one hour after delivery due to acute hyponatraemia caused by excess intake of fluids. She was admitted to a birthing centre as a low-risk labourer where she spent 19 hours including 4 hours in the second stage of labour. Throughout the labour, she was encouraged to drink as per her own initiative and thirst. However, there was no monitoring of fluid intake. In spite of initial confusion about the cause of the seizure, a multidisciplinary approach helped with diagnosis of an underlying pathology and allowed timely treatment to avoid adverse outcomes in this patient. We would like to increase awareness of a possibility, however rare, of water intoxication due to fluid overconsumption by patients in labour and encourage production of information guidance for monitoring of fluid intake of women in labour.