For interest I got a cheap copy of Mary Peters autobiography from Amazon and repeat some of the relevant section here...
"The news came as a bit of a shock when we were told on on arrival at the 1966 Commonwealth Games in Kingston Jamaica that we had to submit to sex tests.
We were all told to report to a building and wait in the corridor outside the room. Everyone was there dressed in their housecoats, school girls of sixteen up to women of thirty-five. It didn't get off to a good start. A woman doctor came out and said "If any of you have got knickers on go and take them off" Of course we all did and bra's too, so had to go back to our rooms and come back naked under our housecoats.
We were called in one by one in alphabetical order, so I had a long wait. The girls who went in didn't come out smiling, and rushed back to their rooms without speaking, no-one gave us a hint of what procedure we might expect in there.
At last my name was called and I went into a bare room which contained two women doctors, one examination couch, and an enamel bowl containing some white cloudy antiseptic, in which the doctors apparently washed their hands after each examination.
I was ordered to lie on the couch and pull my knees up. The doctors then proceeded to undertake an examination which can only be described as a grope. Presumably they were searching for hidden testes. They found none and I left, rushing back to my room without speaking to the ones still waiting in the corridor"
Dr Philip - The UK Play Doctor.