Peripartum hyponatraemia is an under-recognised complication of labour and poses a risk to both mother and baby. It is typically caused by water intoxication for physiological reasons and population health trends around water intake. We have recent experience of managing 2 patients with severe symptomatic hyponatraemia. Both patients had increased their oral intake of fluid during labour as well as receiving intravenous fluids. Dilutional hyponatraemia was found to be the underlying cause in both cases. Initial treatment with hypertonic saline and subsequent fluid restriction rapidly corrected the hyponatraemia though both patients had a prolonged length of stay, required intensive care admission and neonatal assessment and treatment. We have since surveyed our midwifery and medical staff showing gaps in knowledge of this condition 60% not aware of the risk of hyponatraemia in labour, 45% not aware of associated complications and 40% not knowing the most appropriate management strategy. Through a multidisciplinary approach involving endocrinology, obstetric, anaesthetic and midwifery teams, we have introduced a new approach of monitoring fluid balance during labour and checking sodium if fluid intake exceeded >2.5 l or fluid balance is >1.5 l positive. We have introduced a local labour ward guideline for the management of severe symptomatic hyponatraemia in labour and created an education package for all midwifery staff.