The American Society for Reproductive Medicine (ASRM) is a great resource to those with fertility struggles. They have publications designed to help you learn more about your Reproductive Health.
Here is an interesting article on the ASRM website about Male Factor Infertility:
When a couple has trouble having a baby, there’s about a 50-50 chance that the man has a problem contributing to the pregnancy. He might:
1. Produce too few sperm to fertilize an egg
2. Make sperm that are not shaped properly or that do not move the way they should.
3. Have a blockage in his reproductive tract that keeps sperm from getting out.
If you might have a fertility problem, your doctor will want to perform a complete history and physical, as well as several tests to find out what may be causing your infertility.
For the types of diagnostic testing that ASRM recommends, you can read their informational brochure at Diagnostic Testing for Male Factor Infertility.