Egg binding is always a risk, but a good diet with plenty of calcium and vitamin D3 lowers the risk considerably. Getting lots of exercise (including flying/flapping) is also helpful since it helps strengthen the muscles involved in delivering the egg.
Providing the vitamin D is the tricky part since it's hard to get it in natural foods. If she eats pellets she'll get D3 in those. Cooked egg yolk also has D3 and calcium. If she gets outside for direct sunlight it will help her make her own vitamin D - sunlight that passes through a window screen or glass doesn't count. You can buy liquid calcium supplements for birds that have D3 for easy absorption. Here's an example:
http://www.morningbirdproducts.com/prod ... mplus.htmlFull spectrum lights can be a substitute for sunlight, but finding a good bulb is tricky. There's lots of info on this at
http://www.littlefeatheredbuddies.com/i ... hting.html