I am a woman, age 30, from East Asia. A week ago, I got married and had sex for the first time. But after sex I didn't bleed, so my husband thinks that I was not a virgin. As far as I know, there should be bleeding when a virgin has sex. I'd like to know why I didn't.

S.

Not all women bleed the first time they have sex. The hymen is a membrane at the vaginal opening; it has perforations in it so menstrual blood can escape. Sometimes, there is a large central opening. During first intercourse, the hymen may be stretched, rather than torn -- in such a case, there will be no bleeding. Sometimes if the hymen is stretched the first time one has sex, it may tear and bleed later, during more vigorous intercourse.

Sometimes a virgin will have a torn hymen. The hymen can be torn before first sex by tampon use, gynecological exams, a straddle injury (falling on the crossbar of a bike, for example), or other events. If the hymen is already torn, she will not bleed when she has sex for the first time.

You are a virgin if you have never had sex before. Bleeding does not demonstrate virginity.