Progesterone deficiency can cause insomnia and poor sleep which can result in chronic sleepiness and fatigue. A deficiency can also result in anxiety and mood swings. This is why postmenopausal women frequently have poor sleep and anxiety disorders. Routinely, physicians often prescribe estrogen alone without progesterone in women who have had a hysterectomy since almost every cell in the body has progesterone receptors, the entire body responds to this estrogen dominance by causing an increase inbelly fat, weight gain, irritability, insomnia, non-restful sleep and the like. All undesirable to a woman. We always prescribe progesterone with estrogen to prevent these undesirable responses to estrogen alone.