Has your period suddenly slowed down or stopped altogether? Your age has a lot to do with this. If you’re in your 20’s or 30’s, a missing period could signify pregnancy. No matter how much protection you use, find out if you’ve conceived. Women in their 40s or 50s could go through perimenopause, the time approaching menopause. When your ovaries decrease their production of estrogen, your periods start coming less frequently. Periods are also known to get shorter or lighter during perimenopause. When you don’t get your periods for over 12 months in a row, you have reached menopause. The average age is usally around 51.