Transfer of employer - H4 Visa question

[ritbhaskar]

Hi:

I was with an employer on H1B visa when my wife got her H4 visa and came to the US. I have now changed my employer, again on H1B visa. My wife is going to India next year. Does she need to get her H4 visa restamped?

If no, what documents she needs to carry with her?

Thanks a ton for your help!

-Bhaskar