Infertility is a medical condition observed in both sexes, in which reproductive virility is compromised or absent. In males, infertility can be the result of low sperm quality, or a low sperm count. Female infertility can be the result of a wider range of factors, including endometriosis, ovulation problems, tubal ligations, uterine problems, dysfunctions of the fallopian tubes, and advanced age. In some cases, infertility is caused by non-gender-specific problems, including genetics and exposure to certain toxins. Tobacco users of both sexes are at increased risk of infertility. Treatment depends on gender and the exact cause of the problem, and may include counseling, patient education and prescription medications.