My mother is experiencing no menstrual cycle from 3 months...age 48, she has all symptoms of menopause... pregnancy test is negative, is it menopause?

Maybe: A woman reaches menopause when she has not had a menses for 12 months. Prior to menopause is a period of perimenopause that can last for 5-10'years with irregular menses, hot flashes, mood swings, vagina looks dryness, weight gain, fatigue and many other symptoms. A 48yo woman who has missed her period for 3 mo is most likely in perimenopause