Infertility primarily refers to the biological inability of a man or a woman to contribute to conception. Infertility may also refer to the state of a woman who is unable to carry a pregnancy to full term. There are many biological causes of infertility, some which may be bypassed with medical intervention. Women who are fertile experience a natural period of fertility before and during ovulation, and they're naturally infertile during the rest of the menstrual cycle. Fertility awareness metho… (More on Infertility)