No one can look at a girl and tell for sure that she�s had intercourse with a guy. A long time ago�and even today within some religions and cultures�people believed that a girl or woman was a virgin if she had a hymen inside her vagina. The hymen is a thin membrane that partially covers the opening to the vagina in some, not all, women. When a penis enters the vagina, the hymen can tear and bleed. Back then, if a woman had pain and bleeding the first time she had sex, she was considered to have been a virgin.  

But today we know that some women are born without a hymen. We also know that the hymen can be torn or stretched by normal growth and development, tampon use, fingering, bike riding, horseback riding, gymnastics, and other sports. So, a doctor might be able to look at a girl�s vagina and see if she has a hymen or not. But if she doesn�t, there is no way a doctor can know what caused it to tear or stretch. 

Most of the time, a doctor is not allowed to share personal information about you, with your mom or anyone else, without your permission. If your mom forced you to go to a doctor for an examination, the doctor might be able to tell your mom that you no longer have a hymen. But the doctor would not be able to tell her for sure that having sex caused your hymen to tear, since it could have been caused by any of the above reasons.

Most clinics and doctor�s offices have confidentiality policies that prevent them from discussing your personal business with anyone. You can call the clinic or doctor�s office before your visit and ask them about their confidentiality policy.