Mia Farrow before and after plastic surgery.
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Without the before picture, it would be difficult to even recognize her, as she looks today.
I don't recall hearing any reports about her having plastic surgery, but i can't help but think that she must have underwent a few procedures in the last decade.
For one, her cheeks seem very large and unnatural, which leads me to believe she had cheek implants, and her eyes have also changed drastically with a possible eye lift.
And the no brainier would be her plump upper lip, most likely from collagen injections.