Hi,
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PCOS can be treated by the use of insulin modifiers and hormonal contraceptive pills. If the PCOS changes in ovary have improved/reversed with use of medication, you can have chances of having ovulation or egg release from ovary after stopping with hormonal birth control (along with continuation of insulin modifier). If you have engaged in unprotected sexual intercourse after stopping with the birth control pill use, you might be at risk for pregnancy. Consider visiting your gynecologist/obstetrician for further evaluation to see if absent periods are due to pregnancy or post-pill amenorrhea. If pregnancy is suspected, consider getting thorough examination (to confirm pregnancy related changes/signs in body) and blood/serum HCG level test (to confirm/rule out pregnancy accurately). Be regular with your treatment and follow-up with your treating doctor/gynecologist.
Take care.