Blood loss and the frequency of vomiting were assessed at 88 spontaneous vertex deliveries. An i. v. injection of oxytocin 10 u was as effective as ergometrine 0.5 mg in controlling bleeding from the uterus after delivery. The continuous infusion of a dilute solution of oxytocin in the first stage of labour was not followed by an increased blood loss at delivery. Oxytocin infusions were maintained for 1 h after delivery. Vomiting or retching occurred in 13% of the mothers who received i. v. ergometrine. None of the women who received oxytocin suffered emetic sequelae.