I have a valid visa till July 2017 under my old employer. I changed my job six months before and I got approved I797. My wife who’s on H4 visa is planning to visit India in Nov 2016. Her H4 visa is also valid till July 2017. Does she need to go for visa stamping in India? Can she come back to US without visa stamping and just carry approved I797 along with current visa? Please advise.