Suddenly low menstrual flow can be regulated through dietary adjustments, adjusting lifestyle habits, taking medication, surgical treatment and so on. 1. Diet: First of all, you should eat less spicy and cold food, which can reduce the stimulation to the body. At the same time, you can drink more brown sugar water to replenish energy and regulate your body when you have menstruation. 2. Adjustment of living habits: If you are overworked, cold or stay up late when you have your period, it may lead to a decrease in the amount of menstruation. It is recommended to take rest and wear warm clothes when having menstruation, and also pay attention to go to bed early and get up early, and exercise moderately. 3. Taking medication: For low menstrual flow caused by insufficient secretion of estrogen and progesterone, progesterone and ethinyl estradiol can be taken to supplement the estrogen and progesterone drugs for treatment. And for the polycystic ovary syndrome caused by low menstrual flow, can take ethinyl estradiol cyproterone, dydrogesterone and so on to carry on the treatment. 4. Surgical treatment: For low menstrual flow caused by endometrial adhesions due to abortion, surgical treatment under hysteroscopy is usually needed. If the menorrhagia is caused by ovarian cysts, cystectomy can also be performed. In addition, the use of any of the above medications should be under the supervision of a doctor. It is recommended to go to the hospital for examination if there is a sudden decrease in menstrual flow, so that the cause of the problem can be clarified and treatment can be carried out under the guidance of a doctor.