A woman’s doctor prescribes her testosterone

…for better bone density, libido, and mood. The woman is a bit dubious, but readily follows the doctor's orders.

A few days later, the doctor gets a call from the woman. "How are you feeling, Mrs. Smith?" he asks.

She replies, "Oh, just wonderful. I am noticing a positive change on these hormones. I am suffering from a little extra hair growth, though."

"Oh, a little extra hair is perfectly normal when on a testosterone course," the doctor says reassuringly. "Where is the hair growing?"

The woman replies, "On my balls."