Kidney infection

Sexual activity does increase the chances that harmful bacteria that occur naturally in and around the anal and vaginal areas are forced into a woman's urethra to result in a urinary tract infection.  As such, urinary tract infection is not considered a sexually transmitted disease.  Urinary tract or kidney infection can indeed occur in the absence of any sexual activity.  The initial infection usually begins in the urethral-bladder area.  Obstructive uropathy due to structural defects in the urinary tract, or due to the initial infection causes the bacteria laden urine to back flow into the kidneys to cause a kidney infection.  Some women are more prone to UTI or kidney infections than other women.   That means that some women can have sex often and never come down with an infection, while for others, it can occur in the absence of any sexual activity.  Your daughter just happens to be one of the unlucky ones.

Iamjustcurious gave you some sound advice. UTI's can be caused from bacteria being introduced into the vaginal or urethral area. Many sexually active women do have repeated infections as a result of sexual behavior. However, generally the kidneys are not involved. Bladder infections Yes, but kidney, NO. Unless the infection was allowed to fulminate for many months without medication, the chances of it infecting the kidney are rare. Generally a bladder infection in itself is so painful and uncomfortable that to let it  go long enough so as to infect the kidney, is almost unheard of.

A kidney infection is usually a systemic problem and not a by product of sexual activity. Not that it couldn't happen, but highly unlikely that it would.

Get off the sexual aspect of the problem and have further testing done to determine whether or not there may be an underlying problem. An infection that severe had to be raging for months to require hospitalization. I highly doubt a bladder infection was the cause of the severe kidney infection. The other way around, possibly, but the kidneys are the filtering system of the body, they are used to eliminating bacteria from the body. When the filtering system is compromised, it's another story and one that needs to be investigated more thoroughly.

Just to add to the above, it sounds to me as though you don't like the thought of your teen daughter having premarital sex. While you are entitled to your feelings, she is entitled to make her own decisions about something so personal.

Meanwhile, if she is going to continue to have sex (which seems likely) and if she is unlucky enough to be predisposed to urinary tract infections, then there are a few things she can do to lessen her chances of developing another one.

~ Stay hydrated. It is important for everyone, but especially important for women with this type of problem. Water is best, but cranberry juice is also quite good. She should be drinking enough so that her urine output is always clear, never yellow.

~ She should always wear clean underwear. Furthermore, she should avoid wearing non-cotton panties and tight jeans. If she does wear nylon panties and tight jeans, she should make sure not to wear them day after day, but instead to alternate with something looser and of natural fabric.

~ She should remember to always get up to urinate after having sex. If her tendency to get a UTI becomes high, she may even want to wash her pelvic area after she has been intimate. For now, I think just remembering to void and wiping properly (front to back, not back to front) will help.

Here is one site to support the doctor and you; but you can find many others by GOOGLING UTI and sex:

womenshealth.about.com/cs/bladderhealth/a/UTI .htm