Fertility specialists should be alert for undiagnosed endometriosis in women seeking assisted reproductive technologies (ART) before commencing treatment, Australian researchers have warned.

Failure to diagnose the condition prior to fertility treatment makes it more likely that women will use intrauterine insemination (IUI) as their first ART, and this might delay their chances of having a child, they suggest.

The team analysed data from 1322 adults, drawn from the Australian Longitudinal Study on Women’s Health, who had undergone at least one ART cycle by age 42-47 years to determine whether success rates differed between those with and without endometriosis.

One in three participants (35%) had the condition, of which 66% and 34% were diagnosed before or after commencing treatment, respectively, the authors reported in Human Reproduction.