At the time of menopause, women go through a change in their hormonal balance and their fertility. Oestrogen and progesterone (sex hormones) production decreases. This leads on the one hand to shortened deep-sleep phases, and on the other hand to frequent night hot flashes. Both can severely impair sleep.
Internal restlessness and mood swings also develop frequently during menopause. The extensive internal and external changes of this life phase put many women under stress. All these circumstances can lead to sleep disorders. Age also plays a role. The body produces less melatonin sleep hormone and the depth of sleep decreases.