Infertility is defined as the inability of a couple to conceive following 12-24 months of regular unprotected coitus. Sterility is the inability to produce offspring, for example the inability to conceive (female sterility) or to induce conception (male sterility). Primary infertility refers to patients who have never conceived. secondary infertility denotes those that have had previous pregnancies regardless of outcome but have failed to conceive subsequently. Eighty percent of couples can achieve conception within one year of frequent unprotected intercourse while ninety percent do so within the second year. Therefore, 10 percent remain infertile by the end of the second year.