A chemical formula that indicates the simplest numerical ratio of the elements within a molecule, without demonstrating the molecule's chemical bonds or structure. For example, the empirical formula for water is H2O. Synonym: molecular formula.
Pelvic inflammatory disease (PID) is an infection caused by bacteria. When bacteria from the vagina or cervix travel to your womb, fallopian tubes, or ovaries they can cause an infection. Most of the time, PID is caused by bacteria from chlamydia and gonorrhea. These are sexually transmitted infections (STIs). Having unprotected sex with someone who has an STI can cause PID.
You may not be able to prevent PID. It is not always caused by an STI. Sometimes, normal bacteria in your vagina can travel up to your reproductive organs and cause PID. But, you can lower your risk of PID by not douching. You can also prevent STIs by not having vaginal, oral, or anal sex.