Applying H-4, when H1B petition in-review

[mchandr4]

My wife's employer (Indian IT MNC) has filled a H1B petition which is currently under review as per USCIS website. It's been 4 months and we haven't heard anything.

1. I would like to know if it would be wise for my wife to apply for H4 visa as the H1B review continues ?

2. If she applies or gets a H4 will it affect her H1B processing ?

3. Moreover, if she comes to US on a H4 and her H1B get approved should she go back to get stamping to start working or can she apply for a transfer directly ?

I would really appreciate your opinions and responses.

Thank you,

MC