Causes of irregular menstruation? Irregular work and rest Due to the influence of life or work, often stay up late, or reversed work and rest time, this bad work and rest habits can easily lead to endocrine disorders, triggering menstrual disorders. Excessive weight loss Uncontrolled weight loss or excessive exercise may cause the body to not consume enough protein and fat, thus affecting the normal synthesis of estrogen in the body and resulting in low menstrual flow or amenorrhea. Emotional factors If you are depressed, anxious or under great mental stress for a long time, the hypothalamus function will be damaged and the ovaries will not be able to secrete hormones and ovulate, which will easily lead to irregular menstruation. Abortion Multiple abortions can lead to thin endometrium and difficult repair of uterine damage, even resulting in irregular periods, amenorrhea and infertility. Uterine fibroids Women with uterine fibroids usually experience irregular periods, mainly in the form of heavy menstrual flow and extra-long periods. The severity of symptoms depends on the lesion of the fibroids. Thyroid problems If the thyroid gland is hyper- or hypothyroid, it can also affect ovarian function and make menstruation irregular. IUD effects The IUD is a foreign body outside the body and can irritate the endometrium of a woman’s uterus, which can lead to the occurrence of irregular periods and menorrhagia.