Infertility is the failure of a couple to conceive after trying to do so for at least one full year. In primary infertility, pregnancy has never occurred. In secondary infertility, one or both members of the couple have previously conceived, but are unable to conceive again after a full year of trying.
The fertility of a couple depends upon several factors in both the male and female partner. Among all cases of infertility in developed countries, about 30 percent can be traced to male factors, 33 percent can be traced to female factors, 33 percent can be traced to factors in both the male and female partners, and 4 to 5 percent cannot be traced to obvious factors in either partner.


The primary function of HCG (Human Chorionic Gonadotropin) is to increase the synthesis of testosterone. Testosterone results in an increased sperm concentration. Thus the primary efficacy and end point is sperm density and semen volume after HCG treatment. Frequently HCG administration is accompanied by an increase in libido and improved sexual performance.
For men who have been taking testosterone for a long period and experienced testicular shrinkage, HCG will be prescribed and can reverse the effects. This is because HCG jump starts the production of testosterone in the testes and so increases the size of the testicles.