Infertility is medically defined as the inability to conceive following one year of regular sexual intercourse without contraception or after six months if the woman is over age 35.  The definition also includes women who are unable to carry a pregnancy to live birth.  There are two general types of infertility.  Primary infertility is defined as difficulty conceiving for a couple who has never before had a child while secondary infertility describes a couple who is having difficulty conceiving when at least one of the partners has previously had a baby.  According to the 1995 National Survey on Family Growth, approximately 7.1% of married couples were infertile.  If the scope is broadened to encompass the truly desired outcome of an infant, impaired fecundity (difficulty or impossibility of getting pregnant or carrying a baby to term) affects 10.2% of women of reproductive age (6.1 million persons) and 12.9% of married women. In 40% of the cases the problem is attributable to the man, and for 40% of the couples the difficulty is traced to the woman.  In about 10% of the cases, infertility is linked to both partners.  The remaining 10%, despite exhaustive testing, remains unexplained.  The most common causes of female infertility are ovulatory disorders, mechanical problems, endometriosis and some other factors.