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5 Most Common Causes of Infertility

Fallopian Tube Damage or Blockage

One of the many reasons it's so important to get tested for STDs is that some have no symptoms but can make you infertile. Chlamydia and gonorrhea, for example, which are very common, can lead to pelvic inflammatory disease (PID).

PID even sounds painful -- your pelvis should never be described as "inflamed." But when bacteria manage to make it past your cervix and crawl right up into your reproductive organs, that's what happens.

These bacteria can scar the fallopian tubes, making it impossible (or nearly so) for egg and sperm to meet. Even more dangerous, an egg can get fertilized and then completely stuck in the fallopian tube instead of making it to the uterus. The uterus expands to accommodate a growing fetus -- the fallopian tubes simply are not made to do the same and can rupture. This misplaced pregnancy is called an ectopic pregnancy, and it can kill a woman.

The best way to treat PID is as it's happening, and with antibiotics. Unfortunately, once damage is done, it's done, and it can't be fixed.

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