Hello Welcome and thanks for asking In young girls it is very common and called puberty menstrual distrubances for which combined pills are given which contain mild oestrogens and progesterone but you should get investigated first like haemoglobin , Thyroid profile , USG lower abdomen for any ovarian cyst as PCOD is very common these days Pills are to be taken under doctor's guidance If you are overweight try to reduce it , if anemic try to take foods rich in iron supplements Best wishes Take care