Dear Madam, The fullness of labia majora is maintained by Oestrogen hormone. Now it seems that your oestrogen is dropping down causing shrinking of the labia majora. This is suggesting that you may be approaching menopause. You are rather young for menopause, however, variations are noticed. In that case, you may find some variations to irregularities in your menstrual cycle and bleeding. Also you might find sagging down of the breasts also. The other cause of shrinking of labia could be loss of weight in which you are loosing your fat. Labia majora fullness is due to fat. Please report to your gynaecologist to assess your hormonal levels . I hope this helps you, Dr. Nishikant Shrotri