Hello, During the initial phase of life, it is common to get irregular cycles as the hormones try to strike a balance. If this irregularity persists for more than two years, she has to be assessed further. A proper clinical examination, pelvic sonogram, hormone profiles, blood counts and urinalysis are needed. Also, she is overweight and this could be another problem. Please see that she maintains a healthy BMI and exercises regularly. This corrects majority of the menstrual disturbances naturally. Else, hormone correction would be needed. Hope this helps.