hii dear yes stress can affect your menstrual cycle because sometimes stress can changes hormonal level hormonal irregularity can cause irregular periods but you have to rule out other factors also which might be reason of irregular period for stress you have to do like this to reduce stress 1st you have to concentrate over schedule stress free schedule regular exercise meditations and yoga deep breathing exercise progressive muscle relaxation method is very useful. plz read on google for procedure proper sleep healthy diet identify small small risk factor and try to modified it avoid smoking and drinking all of useful to you listening music enjoy your hobbies do pleasurable activities feel free thank u