[The tocolytic activity of melatonin].

Melatonin was shown to produce a tocolytic effect in experiments on the isolated uterine horn in different experimental animals and on the whole body. The ability of melatonin to inhibit uterine contractility was confirmed by the studies of the effects of melatonin on oxytocin-induced myometrial contractions. It may be suggested that the antagonism between melatonin and oxytocin is uncompetitive.