The interaction of parameters of male and female fertility in couples with previously unexplained infertility

A prospective study was undertaken of the relationship between semen variables, serial endocrine and follicular ultrasound measurements in one complete menstrual cycle, and the treatment-independent chance of conception for couples who were referred with unexplained infertility. For the 91 couples studied, the mean length of infertility was 70 months. A 100% follow-up rate was achieved. When a stepwise analysis was performed examining semen variables and ultrasonographic and endocrine variables, the mean ratio of salivary progesterone/plasma estradiol between days +1 and +3, with respect to the luteinizing hormone surge and the Grade 2 motile sperm density, were the only variables that achieved the 5% level of significance. There was a highly significant relationship between the product of these two variables and the chance of conception. This study clearly demonstrates an interaction between parameters of male and female fertility.