Can PID cause infertility if left untreated?

Yes. Pelvic inflammatory disease (PID) can lead to scarring of reproductive organs and cause decreased fertility. PID is estimated to cause around 100, 000 women to become infertile in the US every year. Chances of infertility due to PID become more likely each additional time a woman contracts PID.
Yes. Gonorrhea and chlamydia cause most cases of pid. Untreated PID can lead to chronic pelvic pain, infertility, or scarring of pelvic organs. Adhesions in abdominal organs, such as between liver and the diaphragm, may also develop. Untreated gonorrhea or chlamydia may cause miscarriage or severe and disabling fetal/neonatal infections.