Can you tell me the difference between perimenopause and menopause?

Transitioning. As a woman transitions into menopause, her menses may become lighter and may begin to skip. This transition is the perimenopause and lasts until a woman has not had a period for one year. After one year, we say that the patient is "in menopause" or is "post menopausal".
See answer! Menopause is defined as no period for 12 months. It is as simple as that! peri-menopausal transition is a process that begins in most cases in your late 30's and is characterized by decreased estrogen levels, irregular cycles, and variable symptoms of menopause, such as hot flashes. I hope this helps!