Can a woman have a hormone imbalance even if she has regular periods?

Absolutely: The hormones estrogen and progesterone control the menstrual cycle. Too much estrogen in relation to the progesterone can allow for a regular cycle but also contribute to other symptoms. Increased PMS, moodiness, sleep disturbance, heavier periods, breast tenderness, and uterine fibroids are a few symptoms of this imbalance. Other hormones may contribute depending on symptoms experienced.