Why gender verification tests on women and not men?

Why a gender verification test in the first place? A gender verification test became increasingly necessary in the 1930s when it emerged that some male athletes were competing in female events.

The media fuelled claims that individuals who had competed as women, were in some cases, men. In 1960, at the Rome Olympics, the world athletics governing body, IAAF introduced gender tests for women. Initially the test involved physical examination but this was resented and eventually the IAAF dropped the gender verification test.