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When an egg is released by your ovaries, it travels through these thin tubes to your uterus. Unfortunately, if you've had Pelvic Inflammatory Disease (PID), the passageway can become easily obstructed.
That's why it's so critical to treat reproductive tract infections quickly and prevent scarring and blockage of your tubes. If you were wearing an intrauterine device (IUD) at the time of the infection, the damage might be even more serious.
Finally, blockage of your tubes might be the result of adhesions that form after abdominal surgery.