Infertility means that couples have been trying to get pregnant with frequent intercourse for at least a year with no success. Female infertility, male infertility or a combination of the two affects millions of couples in the United States. An estimated 10 to 15 percent of couples have trouble getting pregnant or getting to a successful delivery. Infertility results from female infertility factors about one-third of the time and male infertility factors about one-third of the time. 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.