However, the infusion rate of oxytocin must exceed 20 mU/minute to cause antidiuresis in humans.19 Hyponatraemia during labour caused by oxytocin administered in electrolyte-free solutions is well recognised, but despite this, hypotonic solutions are often used as a vehicle for oxytocin.20 In our study, fluid volumes needed to administer oxytocin were modest, whereas remaining fluid administration was unrestricted (Table 1). Here, OXT is linked to Hyponatremia.