Normal condition
Pregnancy
Breast feeding
Menopause
Contraceptive
Life style
Low body weight, Anorexia nervosa
Excessive exercise
Stress
Hormone
Polysystic ovarian syndrome
Thyroid function
Pituitary gland, Prolactinoma, tumor, Sheehan syndrome.
Premature manopause
Structure
Uterine scarring "Asherman syndrome "
Lack of reproductive organ.
Medication
