In a lot of cultures, [there are customs and rituals](http://www.soc.ucsb.edu/sexinfo/article/cultural-significance-tact-hymen) upon a woman to losing her virginity, based on bleeding from the hymen, such as using a white bedsheet on the wedding night. If there is blood after intercourse, it 'certifies' that the bride was a virgin.

Do all women always bleed when the hymen is broken in sexual intercourse? 

Is it possible for a virgin who has not previously damaged her hymen to not bleed at all?

Let's assume in all these cases that the hymen was not broken previously due to injury, masturbation, etc.