Why didn't my period come after losing weight successfully?

In the first few days of my menstrual period, proper exercise is beneficial to blood circulation, contraction and relaxation of abdominal muscles and pelvic muscles, smoother discharge of menstrual blood and excellent relief of dysmenorrhea. However, there are exceptions to everything, and sports are no exception. In other words, improper exercise will cause a series of menstrual problems. A large number of sports will cause menstrual disorder, which is based on facts when tracking and studying some female athletes. Excessive weight loss and mental stress during heavy exercise will cause the levels of catecholamine, estrogen and β -endorphin to increase, which will act on neurotransmitters and affect the release of gonadotropins. If gonadotropin can not be released normally, follicle stimulating hormone and luteinizing hormone can not be released normally, it will affect the ovulation function of the ovary, menstruation will become thinner and less, and even amenorrhea will occur.