Fig. 1From: Melatonin improves the first cleavage of parthenogenetic embryos from vitrified–warmed mouse oocytes potentially by promoting cell cycle progressionFlowchart of experimental design. Melatonin (10− 9 mol/L) was added in warming, PA and in vitro culture media before the embryos moved into the 2-cell stage of development (24 hpa). hpa: hours post-activationBack to article page