My advice is don't put her on Depo. It is aweful. It not only made me feel like crap literrally, but it's actually very bad for the body. It saps your bone density and many, many women later have fertility issues. There are thousands of forum posts about it that I stumbled across when it was making me sick. The longer you are on Depo the more likely it seems to make you infertile.

So despite the convenience, I am anti-depo.

I don't think they will put an IUD unless you have had a baby. Best to talk to her GYN and see what they recommend for forgetful girls. I was on pills for about two years and I forgot them a lot, so I know what it is to be forgetful.