May 1, 2000 (Reno, Nev.) -- Besides vulvar vestibulitis, other conditions can cause pain during intercourse. If you have this complaint, see your doctor, who will first rule out yeast or other infections and then investigate other possible causes.
Inadequate lubrication within the vagina can cause pain. Normally, a woman's vagina secretes lubricating fluid when she is sexually aroused, but menopause, breastfeeding, tension, and certain prescription drugs can hamper this process. Creams, jellies, or vaginal suppositories are recommended. (Beware: Oils or petroleum jellies can dissolve latex condoms.)
Pain deep inside the vagina can be a sign of such problems as ovarian cysts, infection of the uterus or fallopian tubes, endometriosis (a condition in which menstrual tissue flows back through the fallopian tubes and begins to grow outside the uterus, usually in the abdominal cavity), or scar tissue from an old infection or previous surgery. Your doctor may perform a laparoscopy (examination with a thin tube-like camera through a small incision in the navel) to determine what's wrong.
A tilted uterus can also cause pain if your partner's penis strikes your cervix or uterus during sex. This is usually present from birth and normally does not cause any other problems.
Sometimes pain is caused by vaginismus, a condition in which the muscles of the vaginal wall involuntarily spasm. Physical therapy may be helpful.
this is off of web md, but maybe it will help, she should see a doctor, in my opinion.
other than a yeast infection, she could have a bacterial infection called bacterial vaginosis, which is apparently as common as a yeast infection, and can cause some pain.
also, just like puddles said, some positions can cause pain if you are thrusting too deep or strong.
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Now my fantasy is ruined...
