Amenorrhea is the absence of a menstrual period in a woman of reproductive age. There are two types of amenorrhea: primary and secondary amenorrhea. Primary amenorrhoea is the absence of menstruation in a woman by the age of 16. On the other hand, secondary amenorrhea is where an established menstruation has ceased for three months in a woman with a history of regular cyclic bleeding, or six months in a woman with a history of irregular periods. This may cause serious pain in the back near the pelvis and spine. This pain has no cure but can be relieved by doses of progesterone.
Secondary amenorrhea may be due to pregnancy, anovulation, menopause, or premature menopause, Hypothalamic-pituitary dysfunction ( which include exercise amenorrhoea, stress amenorrhoea, eating disorders and weight loss), hyperprolactinemia, polycystic ovary syndrome, drug-induced, or thyroid dysfunction.
It would be best to see your doctor or gynecologist for further evaluation and proper management. A complete physical and gynecologic examination is important to reach a diagnosis.
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