One of the main chemical culprits for menstrual cramps is a rise in prostaglandins[1] (especially PGF2ɑ), which can reduce blood flow to the uterus while also strengthening contractions. This combination lowers oxygen availability in the uterus, resulting in cramping and pain. Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can stem this rise in prostaglandins, which is probably why they are effective for treating menstrual cramps[2] and are recommended[3] as a first-line intervention.
What causes pain from menstrual cramps?
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•Last Updated: May 16, 2025
Menstrual cramps are primarily caused by an increase in prostaglandins, which reduce blood flow to the uterus and enhance contractions, leading to decreased oxygen availability and pain. Nonsteroidal anti-inflammatory drugs like ibuprofen can effectively reduce prostaglandin levels, which makes them a recommended treatment for menstrual cramps.