Premenstrual syndrome (PMS) is a combination of symptoms that can affect your body, your mood, and how you act in the days before your menstrual period. Most women have tender breasts, bloating, and muscle aches a few days before their periods. These are normal premenstrual symptoms. But when symptoms disrupt your daily life, they are called PMS.
Some women first get PMS in their teens or 20s. Others don't get it until their 30s. The symptoms may get worse in your late 30s and 40s, as you approach perimenopause.