HI, thanks for using healthcare magic Myfol is methyfolate which is one of the vitamins. It is very useful in women who are trying to conceive because it has been shown to be needed in the first trimester of pregnancy to prevent spine problems in babies. It has not been proven to be helpful with irregular periods however for most persons. You may want to have blood tests and imaging such as ultrasound to determine the cause of the irregular periods. The most common causes are: (1)polycystic ovarian syndrome- ultrasound would see cysts by the ovaries (2)side effect of medication such as contraceptive (3)emotional illness or stress (4)high levels of prolactin hormone (5)physical illness (6)abnormal levels of thyroid hormone Treatment would depend on the cause found. I hope this helps