Premenstrual syndrome (PMS) is usually caused by fluctuating hormones just prior to menstruation. More specifically, excess estrogen during the luteal phase is often to blame for the various symptoms that many women get during PMS. Thus, when estrogen does not decrease in response to rising levels of progesterone, symptoms like breast tenderness and mood swings can result. While there are various medications available to treat the symptoms of PMS, there is no drug available to balance the hormones, which often means that premenstrual syndrome cannot be prevented.
What happens to the hormones during PMS is often easier to understand when the different phases in the cycle are explained. The first day of the period begins the follicular phase, during which estrogen is the dominant hormone. It ends after about two weeks, culminating in ovulation, which is typically when the egg is released from the ovary. Once ovulation has passed, the luteal phase begins, which is typically dominated by progesterone. In women with particularly extreme premenstrual syndrome symptoms, estrogen is one of the prevailing hormones during PMS, even during the time that it is supposed to decrease to make room for progesterone.
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Thus, the imbalance of hormones during PMS is often to blame for the various symptoms that many women regularly get. One of the most common signs of premenstrual syndrome includes mood swings, causing many women to feel depressed or irritable for no particular reason. Many women also feel exhausted, yet may have trouble sleeping. Of course, there are some physical changes, as well, such as bloating, acne, and larger breasts that feel sore. The length of time that women experience such symptoms largely depends on how long the imbalance of hormones during PMS lasts, which means that some women have to endure them for more than a week before menstruation while others may only notice them for a day or two.
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There are medications on the market that aim to relieve some of the most common symptoms, but they cannot completely cure premenstrual syndrome. This is because there is no surefire way to balance out the hormones during PMS. Additionally, it should be noted that the symptoms tend to get worse over time, which means that young women who do not experience them may start noticing them as they get older. The good news is that the only way to tell that the hormones are not balanced is through the signs of PMS, which is why most women are satisfied to just treat the symptoms.