The menstrual cycle differs from woman to woman. While a 28-day cycle is often thought of as the ‘standard length’, most women have cycles ranging between 21–35 days.
Girls in their early teens often experience irregular menstrual cycles which might range between 21–45 days.
If you are having period irregularities – for example your periods haven’t come for more than 90 days, they continue even after seven days or come before 21 days or after 35 days of the last period – it is time for you to consult a doctor. They will be able to help you with the best treatment.