None, and out of curiosity I just searched the school directory for my kids' DC charter school and there were none on there.
There is a popular kids' book series called Ivy & Bean. Also it's Beyonce's older daughter's middle name.
You can see from this chart
http://www.babynamewizard.com/baby-name/girl/ivy that it last peaked in popularity in the 1880s, has been increasing in popularity pretty rapidly since 2008, but is still below #100 on the SSN name charts. It wouldn't be shocking if it continued that trajectory and became relatively more popular in high-income areas like Bethesda since it fits a lot of modern trends in baby names for affluent white people--somewhat unusual, a charming "old lady name" vibe, lots of vowels.
Anyway, OP, it is a great name and if you like it, you should go for it. There's no way to avoid having any other kids with the same name as your kid, or it blowing up in popularity after you pick it, or Disney naming a movie character your kid's name. The important thing is that you like the name.