CXCL8 and Infertility: The concentration of IL-8 in follicular fluid was positively associated with intrauterine pregnancy (adjusted for age, cause of infertility, rate of good-quality embryos transferred, and endometrial thickness r = 207.5 pg/mL, P = 0.051), and also with parity (adjusted for age and cause of infertility r = 150.6 pg/mL for every child born, P = 0.039).