Yeah, female (and male) parakeets need calcium supplements and cuttlebones galore when they are breeding. Having babies and laying eggs is very straining and stressful to them and they need calcium ... and fresh foods never hurt either. Also, female parakeets will eat the membrane of an egg once the baby hatches out because it tastes very good to them. So don't be woried if she is chewin on the egg shells after the babies hatch.
What else did the vet do and/or say?