What complication can arise in untreated pelvic inflammatory disease?

Infertility is a significant complication that can arise from untreated pelvic inflammatory disease (PID). PID often results from sexually transmitted infections that ascend from the vagina and cervix into the upper reproductive organs, including the uterus, fallopian tubes, and ovaries. The inflammation and scarring caused by PID can lead to blockages in the fallopian tubes, preventing the passage of eggs or sperm, ultimately impairing fertility.

When PID is not treated, the persistent infection and inflammation can cause anatomical and functional disruptions within the reproductive system, significantly increasing the risk of infertility. This is especially critical since many individuals may not experience noticeable symptoms during the early stages of PID, leading to delayed diagnosis and treatment.

The other options do not directly relate to complications that arise specifically from untreated PID. For instance, menstrual irregularities can occur for various reasons, but they are not as closely linked to PID as infertility. Hyperthyroidism and diabetes are endocrine disorders with different underlying causes that do not originate from PID. Thus, the relationship between untreated PID and infertility is well established and serves as a critical consideration in reproductive health.