A few years ago I had to get an x-ray done. Of course, the usual questions about pregnancy came up:

Nurse, "Do you know if you are pregnant?"
Me, "I am certain I am not."
Nurse, "Are you 100% certain? We can test you for pregnancy if there is any doubt."
Me, "I am 100% certain."
Nurse, "Are you in a committed relationship?"
Me, "Yes, I am."
Nurse, "What method of birth control are you using?"
Me, "None"
Nurse, "How can you be certain, then, that you are not pregnant?"
Me, "Because the other person in this relationship is a woman."

I was quite offended, not really sure why, but soon realized that this was not the last of similar questioning in my life...