Assessment of the cause of infertility.

The different causes of infertility and evaluation of the infertile couple are reviewed in this paper. Forty to 50 percent of cases are due to male factors, and special emphasis is placed in describing techniques to diagnosis this type of infertility. Five to ten percent of infertile couples have infertility of unknown etiology even after a complete, appropriate evaluation. Special instruction in how to diagnose and treat these types of patients is described. A step by step evaluation of peritoneal factors, ovulation factors, and male and cervical mucus interaction is presented for the clinicians' use.