Since OHSS is closely associated with the excessive production of ROS and melatonin is supposed to be a powerful radical scavenger, the objective of this study was to investigate whether SESN2 are induced in OHSS and whether melatonin can alleviate oxidative stress in OHSS as well as the potential role of SESN2 in OHSS. This evidence concerns the gene SESN2 and ovarian hyperstimulation syndrome.