When I was pregnant I was laid up on bed rest for about 7 weeks. My sweet husband went to go get me something to read, and not knowing what I would like, picked out some Star Wars novels. I thought it was a strange choice at the time, but went ahead and read them. To my surprise, and delight, they were very enjoyable. One of the aspects about the force the book highlighted was that each person had an unique strength with it. One might be wisdom, healing, so forth. Perhaps Leah, as an infant in the womb, was able to sense her mother's presense and feelings, if that sort of thing were her strength. Just a thought.
This may be true, but Lucas does not bring that out in the later epsisode... lots of unanswered questions calling for an Episode 3 1/2!