Premenstrual syndrome (PMS) refers to a wide range of physical and emotional symptoms that occur in the 1–2 weeks before your period. These symptoms are caused by hormonal fluctuations — particularly the drop in estrogen and progesterone — in the luteal phase of your cycle.
PMS affects up to 75% of menstruating women to some degree. For about 5–8% of women, a severe form called Premenstrual Dysphoric Disorder (PMDD) causes significant disruption to daily life and requires medical treatment.
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