Honestly, if you feel it's fine, take her. Maybe just start her on a glucosamine/chondroitin supplements to support her joints. When I got Nova my vet told me that it's important not to stress their joints when they are young (I had asked about doing agility), and I saw the same things when I researched it. Low impact exercise and letting the dog deciding when they've had enough were what was reccomended most often by the people I talked to and articles I'd read.

It's my opinion that joint problems in young dogs is mostly genetic related, but if the dog's joints are already bad, forced exercise will make it worse. It might be a good idea to x-ray her hips when you spay her. If I hadn't done that I wouldn't know that Nova was dysplastic, because she doesn't show any signs right now.