Pelvic Inflammatory Disease

Definition

Pelvic Inflammatory Disease (PID) is an infection of the female upper genital tract, including the uterus, fallopian tubes, and ovaries, often caused by ascending sexually transmitted or endogenous bacteria, leading to inflammation and potential long-term reproductive complications.

Epidemiology

• Common in sexually active women aged 15–24 years
• Incidence higher in women with multiple sexual partners or history of STIs
• Risk factors include previous PID, IUD insertion, douching, and low socioeconomic status
• Frequently underdiagnosed due to variable presentation
• Significant cause of infertility, ectopic pregnancy, and chronic pelvic pain

Etiology

• Polymicrobial infection: sexually transmitted pathogens (Chlamydia trachomatis, Neisseria gonorrhoeae) and endogenous flora (Gardnerella, anaerobes, E. coli)
• Post-procedural or post-partum infections (post-abortion, post-delivery, post-surgery)
• Risk factors: multiple sexual partners, unprotected intercourse, recent gynecologic procedures
• IUD insertion carries a small increased risk in the first 3 weeks post-insertion

Pathophysiology

• Bacteria ascend from the lower genital tract to the endometrium, fallopian tubes, and ovaries
• Inflammation leads to edema, infiltration of neutrophils, and tissue damage
• Formation of tubo-ovarian abscesses in severe cases
• Scarring and adhesions may occur, leading to infertility or chronic pain
• Systemic inflammatory response may result in fever and malaise