The effect of morphine and naloxone administration on plasma oxytocin concentrations in the first stage of labour.

OBJECTIVE We investigated the effect of an opiate (morphine) and an opiate antagonist (naloxone) on the maternal secretion of oxytocin in the first stage of labour. DESIGN Patients were randomized to receive either morphine 5 mg (n = 9), naloxone 1.2 mg (n = 10) or sterile water (n = 9) which was injected intravenously. PATIENTS Healthy women in the… CONTINUE READING