Male infertility is a factor in nearly one-third of Australasian assisted reproductive technology cycles, but the cause in most cases is unknown, epidemiologists say. 

A new report captures data on every assisted reproductive technology (ART) treatment cycle performed in Australia and New Zealand in 2020, including, in a world first, detailed information where the causes of male infertility were known. 

The team from UNSW’s National Perinatal Epidemiology and Statistics Unit found that male infertility was the reason for 20% of 80,000 ART cycles by female–male couples, while 11.7% was due to a combination of male and female factors.

Infertility was unexplained in 28% of all cycles and female infertility accounted for 36% of cycles.