The side effects of menopause are generally caused by a fluctuation in hormone levels. Below is a list of causes of menopausal fatigue and dizziness. Estrogen deficiency. A lack of estrogen can cause insomnia and thus lead to fatigue, dizziness, mood swings, depression, and an inability to concentrate. Progesterone deficiency. The decrease in progesterone during menopause can result in hormonal imbalance that lead to feelings of sickness and fatigue.