The relation between plasma oestrogen, progesterone and prolactin concentrations and the efficacy of vaginal prostaglandin E₂ gel in initiating labour

In an attempt to relate the efficacy of treatment to endogenous hormone levels, plasma oestrogen, progesterone and prolactin levels were analysed in women at term following the vaginal administration of prostaglandin E₂ gel to induce labour. Patients who went, into labour after treatment had significantly higher oestradiol‐17β levels before treatment compared with those requiring formal surgical in‐duction the following day. No difference could be demonstrated in levels of progesterone or prolactin in the two groups of patients. The significance of these results is discussed.