Possible causes of irregular menstrual cycles include uncontrolled diabetes, eating disorders, hyperthyroidism or hypothyroidism, hyperprolactinemia, certain medications, and perimenopause, according to the National Institute of Child Health and Human Development. Excessive weight loss or gain, emotional stress, and hormone problems can also cause menstrual irregularities, reports WebMD.
Normal menstrual cycles range from 21 to 35 days, explains Cleveland Clinic. However, menstrual periods are often irregular during the first and last few years of menstruation, notes WebMD.
A woman should maintain a healthy lifestyle and practice stress reduction and relaxation techniques to reduce the risk of menstrual irregularities, advises Cleveland Clinic.