Hi my mum is 49 and hasn't had a period for over 10 weeks now.not pregnant, could this be the change?

Absolutely. There are many women who go thrugh the change at 50. She could be a little early.

She could very well be going through menopause. The average age of women who start menopause is 51. Perimenopause will mean that she has not had a period in over 6 months. Menopause means that she has not had a period in a year.

If there is any cause for concern, she should see her doctor for a proper diagnosis.