Facial hair in women isn’t always a sign of medical issues, but certain types of hair can be a red flag.

Doctors may also want to rule out issues like Cushing’s disease or certain adrenal conditions, noted Sistla. “Those are all rare.”

“The vast majority end up being either polycystic ovarian or something called idiopathic hirsutism, which is essentially, we check for all these things, and if all of it comes back negative, then we assume that we don’t have a cause that we identify. It could be something that runs in the family or, again ... ethnicity dependent,” said Sistla.

This article originally appeared on HuffPost.