When you are in your mid-30's, your ovaries begin to change how much estrogen and progesterone, two female hormones, they make. These are both important for normal menstrual cycles and successful pregnancy. Estrogen helps to keep bones healthy. It may also have an effect on cholesterol levels in your blood, help keep skin and arteries more elastic, and possibly help memory. Although very rare before the age of 40, menopause can happen anytime from your 30's to your mid-50's or even later.
Smokers often begin menopause earlier than non-smokers.
Once your uterus is removed, your periods will stop. This is the age when body changes begin and breasts develop. This probably begins about 3 to 5 years before your last menstrual period. It lasts until 12 months after your final period. Some signs or symptoms of menopause may appear during this time.