Peripartum hyponatraemia is a potentially serious and often under-recognised condition that can affect women and birthing people during labour and immediately after birth. This module is designed to develop understanding of the causes, risks, and clinical signs of hyponatraemia in the peripartum period. Through an exploration of the physiology, risk factors, and symptoms, this module empowers maternity staff with practical knowledge to support prevention, early detection, and appropriate escalation — ultimately contributing to safer care for mothers and babies.