FSHB and Infertility: Binary logistic regression analysis corrected for confounders (Age, infertility duration, infertility type, infertility cause, AFC, AMH, bFSH, BMI, Ovarian stimulation protocol, Gonadotropin dosage, E2 on the day of HCG inj, No of oocytes retrieved, fertilization methods, No of 2PN, No of transferable embryos on D3, No of cycles without frozen embryos), early blastocysts were a risk factor for biochemical pregnancy (OR = 0.390, 95%CI = 0.195–0.779, P = 0.008).