Have you heard of mittelschmerz?

Mittelschmerz is another type of pelvic pain and fortunately it doesn't require more than taking over-the-counter pain relievers and possibly an oral contraceptive.

Mittelschmerz means "middle pain" (in German), because it occurs about halfway through the next menstrual cycle. It is pain during ovulation. It is a one-sided lower abdominal pain that might switch sides the next month. The pain varies: It may be sharp or dull; it may last a a few minutes, but it may continue for hours or days.

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