Infertility is the inability to get pregnant after a year of unprotected intercourse. About 10% of couples in the United States are affected byinfertility. Both men and women can be infertile. According to the Centers for Disease Control, 1/3 of the time the diagnosis is due to female infertility, 1/3 of the time it is linked to male infertility, and the remaining cases of infertility are due to a combination of factors from both partners. For approximately 20% of couples, the cause cannot be determined. The main symptom of infertility is the inability of a couple to get pregnant. A menstrual cycle that's too long (35 days or more), too short (less than 21 days), irregular or absent can be a sign of lack of ovulation, which can be associated with female infertility. There may be no other outward signs or symptoms.