Infertility is defined as the inability to get pregnant after 12 months of trying for women under 35 years of age, and after 6 months of trying for women 35 years of age and older. About 80% of infertility is caused by one these three problems: Ovulation problems: is she ovulating regularly and are her eggs OK? Sperm problems: does he have enough and good sperms? Fallopian tube problems: are her fallopian tubes open?