PMOS: Symptoms, Causes, and Treatment Options

PMOS, or polyendocrine metabolic ovarian syndrome, is one of the most common hormonal conditions affecting women of reproductive age. It can cause irregular periods, excess hair growth, weight changes, insulin resistance, and fertility challenges—but symptoms vary widely from person to person. Women's health expert Kirtly Jones, MD, explains what PMOS is, why it happens, and how birth control pills are often used to manage periods and hormone-related symptoms. Learn when lifestyle changes may help, when medication may be the better option, and when to seek specialist care.   Please note: Polycystic ovary syndrome (PCOS) was renamed polyendocrine metabolic ovarian syndrome (PMOS) in May 2026. The new name more accurately reflects the condition’s complex hormonal and metabolic effects. Because this terminology is still being adopted across health care organizations, research publications, and educational resources, both terms may appear throughout our content. In most cases, PCOS and PMOS refer to the same condition.