The following 11 independent variables were entered into the multivariate regression analysis of live birth: age, BMI (underweight, normal, overweight or obese), infertility duration (< 1 vs. ≥ 1 year), infertility type (primary vs. secondary), infertility cause, endometrial thickness, number, stage and quality of transferred embryos, cryopreservation time, and LH surge (yes vs. no) (Table 3). The gene discussed is PLOD1; the disease is Infertility.