The Effect of Intra‐amniotic Oestriol Sulphate on Uterine Contractility at Term

Summary A double blind trial of the effect of oestriol sulphate on myometrial contractility was performed on 20 post‐mature primigravidae. One half were given oestriol sulphate by intra‐amniotic injection and the others the solvent vehicle only. The effect of these injections on spontaneous uterine activity was observed for four hours. The membranes were then ruptured and recordings of uterine contractions were made for a further five hours in order to determine whether pre‐treatment with oestriol affected the response of the uterus to rupture of the membranes. The oestrogen‐treated group did not differ from the placebo group either in endogenous activity or in response to rupture of the membranes.