It is a call from the Brigham's and Women's Hospital in Boston. It is the "appointment confirmation number" and is sometimes automated and sometimes run by a "real person".
Often they misdial the number as I have gotten calls from them reminding me of an appointment I've never had...as I am a guy...and never been to that hospital.
They have called me a few times since yesterday. I only answered once and said hello a few times but there was no response and it didn't even sound like there was anyone breathing on the other end. My friend called back and it went to voicemail.