A doctor is doing routine breast examinations at a college. The first girl comes in, takes off her blouse, and as she does, the doctor notices that the girl has a red 'H' imprinted in her stomach. After the examination, the doctor asks the girl how the H came about.

'Well,' she says,' my boyfriend is from Harvard, and he's so proud of the school that he never takes off his Harvard jumper, even when we make love.'

'Fair enough' thinks the doctor as the girl leaves. But the doctor is surprised when the next girl takes off her blouse and has the same thing, except hers is a red 'Y'. again the doctor asks how it came about.

'Well,' she says, 'my boyfriend is from Yale, and he's so proud of the school that he never takes off his Yale jumper, even when we make love.'

The doctor is fascinated by this. The next girl enters, takes off her blouse and the doctor sees that on her stomach is a red M.

'Ah, ' says the doctor, 'A boyfriend in Michigan?'

'No,' replies the girl, 'A girlfriend in Wisconsin. why do you ask?'