Background: Infertility is one of the most prevalent health disorders in young adults.

Objectives: To study the distribution of causes of infertility in couples referred to primary infertility clinics in Israel.

Methods: Data for a 9 year period were derived from two clinics of major women's hospitals run by the country's largest health insurance funds. All patients were treated by one physician. Laparoscopy was not performed to rule out endometriosis.

Results: Of the 2515 couples identified, 1991 (79.2%) had a definitive diagnosis following complete workup (including hysterosalpingography). Mean age was 29.6 ± 6.0 years; mean duration of infertility was 1.7 ± 1.8 years. Primary infertility accounted for 65% of cases. Causes of infertility were male factor (45%), oligo-ovulation disorders (37%), and tubal damage (18%). Infertility factors were identified in the woman alone in 30.6% of cases and the man alone in 29.2%. Two combined infertility factors were found in 18% of patients, and three combined factors in 0.5%. The rate of unexplained infertility (which probably includes non-tubal endometriosis) was 20.7%.

Conclusions: As male factor accounts for almost half of all cases of infertility in couples, sperm analysis is mandatory before any treatment.