It is hard to see from the pic but it does look to have a small abdomen and I can see the lack of hair there and on the legs. The lack of hair will fix itself with the next molt. Does she kick a lot and are you sure it is definately a female? Also, if she is eating good I would personally feed her twice a week until she get's her weight up and gets back on track

http://www.arachnoboards.com/ab/showthread.php?t=145048