What is the difference between menopause, perimenopause and post-menopause?

Perimenopause — In this first stage, hormonal production of estrogen, progesterone and other reproductive  begins to shift and symptoms first appear and may become frequent and severe. Perimenopause can start as early as age 35, but for most women, usually begins in the mid-to-late 40s. Menstrual cycles continue but may become irregular.

Menopause — This culminating stage is confirmed by the stopping of monthly periods for at least 12 months. Hot flashes and other symptoms continue if underlying hormonal imbalances are not addressed. The average age for menopause is 52.

Post-menopause — In this “after menopause stage,” a women’s hormones establish new patterns now that they’re no longer needed to support reproduction. Women entering post-menopause with hormonal imbalances often see their menopause symptoms persist — even years after they have stopped menstruating.