Brief Answer:
It is because of hormonal imbalance.

Detailed Answer:
Hi,

I have gone through your history and understand your concerns.
Menstrual irregularities in your case, could be due to hormonal imbalance cause by PCOS.
PCOS is a endocrinal disorder in which hormonal imbalance will be there due to cyst in ovary ,facial hair growth and weight gain maybe there
As it is a lifestyle disease ,you have to change your lifestyle, eat high protein diet with lots of vegetables and fruits and exercise regularly.
Get your hemoglobin,HbA1c and TSH level.
No need to worry about it and take progesterone for withdrawal bleeding.
Hope found useful, feel free to ask more information.
Good luck
Regards

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