Sir she said that her last two menstrual dates are 1st january and 3rd February and she is expecting that her next menstrual date will may be 5th march. So tell me her safe period and clearly learn us how to calculate? She is also telling that her menstrual cycle are not continuous. It sometimes 1 to 4 day (s) more than 30 days and sometimes below. Is it a problem of her? Please sir answer me. Thank you.