PID or Pelvic Inflammatory Disease is an infection of the upper reproductive tract, which includes the Uterus, Fallopian tubes, and ovaries. It is a life threatening disorder in some cases, however its affects are not just acute. PID actually can result in scarring of those tissues, making it difficult to conceive, as a fertilized zygote may not not join with the walls.
Although Endometriosis might seem like a close fit, it doesn't scar the tissues. Instead endometriosis results as Endometrial tissues (the tissue that forms in preparation for pregnancy in the uterus) forms in places outside of the Uterus.
