Infertility is quite common. On average, 10% of couples within reproductive age are unable to get pregnant or carry a pregnancy to term. 9% of men and 11% of women have experienced problems with fertility.
5%–10% of infertility is caused by unexplained factors. This is usually when the doctor is unable to diagnose the exact cause. It may be due to problems with the sperm quality, egg quality, or health.