What is a serious complication of STIs that may lead to infertility?

Pelvic inflammatory disease (PID) is a serious complication of sexually transmitted infections (STIs) that can significantly impact a person's reproductive health and may lead to infertility. PID occurs when bacteria, often from STIs such as chlamydia or gonorrhea, ascend from the lower genital tract into the uterus, fallopian tubes, and pelvic cavity. This infection can result in scarring and damage to these structures, which can disrupt normal function and lead to difficulties in conception.

Infertility can arise as a direct consequence of the damage caused by PID, such as blocked fallopian tubes or other structural changes, which prevent egg fertilization or implantation. In some cases, PID can lead to chronic pelvic pain and ectopic pregnancies as well.

While chlamydia and gonorrhea are specific STIs that can lead to PID, their presence alone does not directly indicate infertility. Endometriosis, while it can impact fertility, is a separate condition related to the presence of endometrial tissue outside the uterus and is not a complication of STIs. Thus, PID stands out as the primary condition directly linked to the infertility risk associated with untreated STIs.