What physiological process primarily causes primary dysmenorrhea?

Primary dysmenorrhea is primarily caused by the release of prostaglandins from the endometrium. Prostaglandins are hormone-like substances that play a significant role in the menstrual cycle, particularly in the process of menstruation. When the endometrium sheds during menstruation, it releases prostaglandins, which lead to increased uterine contractions. These contractions can cause pain and discomfort, which are the hallmark symptoms of primary dysmenorrhea.

The biological mechanisms involved in this process include the contraction of the uterine muscles, which can reduce blood flow and oxygen to the uterus, resulting in ischemic pain. As levels of prostaglandins rise, so does the intensity of these contractions, thereby intensifying the pain experienced during menstruation.

Understanding the role of prostaglandins is crucial for managing primary dysmenorrhea, as treatments often focus on reducing prostaglandin production or mitigating its effects, such as through the use of non-steroidal anti-inflammatory drugs (NSAIDs) or hormonal contraceptives.