The mass spectrometer was used to identify the labeled samples from electroacupuncture treated and Ovarian Hyper-stimulation Syndrome (OHSS) group. The ovarian proteins from four biological replicates in each group were extracted using the phenolic extraction method, iTRAQ labeling and quantitative LC-MS proteomics were performed according to the manufacturer's instructions. The quantitative protein ratios were weighted and normalized by the median ratio in Mascot. When the differences in protein expression between the two groups were >1.2-fold or <-1.2-fold (with P < 0.05), the protein was considered to be differentially expressed.