What would be the point of two different types of birth control at once?

Okay so I was hanging out with my SOs little sister, she’s 19 and she was asking me how to get rid of her bad acne because I used to have acne and now my skin is clear and she wants to know my secrets. My secret is birth control so I told her that and she said “oh I’m on the pill and the IUD.” I said “you’re WHAT?”

“Yeah I’m on two different kinds on birth control, IUD and the pill because I have a lot of issues.”

I said “that is more than likely the cause of your acne. All the hormones are coming out of your skin.” And she said “that makes sense because it didn’t start until I started taking the pill because I have the Mirena and my skin was fine just on mirena, but now I am on the pill too and my skin is horrible.”

I told her to talk to her doctor about it. And possibly find a new doctor.

Y’all why on earth would a doctor put a young girl on two different forms of hormonal birth control? One birth control by itself has its risks but good god.

See if have a lot of issues myself, endo and PCOS and no doctor has ever said take a pill and an IUD