A Retrospective Study on the Effect of Male Progressive Sperm Count After Semen Pretreatment on ICSI Fertilization Outcome

The investigators plan to retrospectively analyze clinical data from 14,189 fresh ICSI cycles in Reproductive and Genetic Hospital of CITIC-Xiangya from January 2016 to December 2017.The investigators will regard total progressive sperm number of 2 x 10\^6 after pretreatment as the boundary value, and will divide total progressive sperm number of 2 x 10\^6 after pretreatment into 2 x 10\^6 or higher and \< 2 x 10\^6 groups, and will further divide \< 2 x 10\^6 group into: = 0, (0,10\^6\], (10\^6, 2 x 10\^6) three groups. Propensity score matching will be used to balance the baseline data between four groups. The matching variables are age, female BMI, AFC, AMH and ICSI.