My wife's H4 visa is in review stage; can she travel to India on her current L2 visa?

It depends if the H4 was filed before the L2 expired. Also, even if not, she will need to pick up the actual visa at the U.S. Consulate.

Travel abroad during the pendency/adjudication of a non-immigrant visa Change of Status petition can be deemed by USCIS under the current Regulations to be an "administrative abandonment" of the pending petition. We caution our own clients to avoid travel abroad during such transition periods if at all possible.

Sounds like her travel will abandon the application. If an application for change or extension of status is pending review, an applicant's departure from the US generally constitutes an abandonment of such status. While the applicant may remain in the US after the expiration of the last valid I-94, the departure from the US pending a decision will automatically constitute abandonment of the application. My suggestion is that you speak with someone knowledgeable about the case before making travel plans because you do not want to depart the US only to find out that your wife is stuck outside of the country waiting for your petition to be approved before she can make an application through the US Consulate to return to the US. While this does not appear to be all that complicated of a case, you do want to make sure that you understand the potential consequences of departing the US before traveling. Wait times to obtain nonimmigrant visas through the US Consulates in India can be lengthy and you do not want a situation where a brief visit turns out to be a long period of absence. The answer is out there, you should speak with someone before hand to ensure that you have that answer before travel. Good luck.

If the USCIS checks the records of the Customs and Borders Protection before granting your wife's application for change of status, it will reject the application as abandoned because the applicant left the U.S. If it happens, it would not interfere with your wife's ability to come back on her L2 (so long as you are still working for your L1 petitioner) and re-file the change of status application. If the approval of your H1 comes while she is in India, she should make an appointment at the U.S. Consulate and receive her H-4 there - because, technically, her L2 disappears the very same moment when your L1 is changed to H1.

Since it is a change of status petition that you filed, if she leaves the US, she essentially abandons the petition. She would then need to either get a H-4 visa prior to returning to the US or enter in L-2 status and resubmit the change of status to H-4 when she returns.

From what you have described if she travels now she would need to either do consular processing for the H-4 or if you aren't in H-1b status at the time of her return, reapply for a new change of status request upon her return.

Your wife's petition to change her status from L2 to H4 will not be deemed abandoned for traveling. However, if approved while she is traveling she will need to take the approval notice to the US Consulate in India to apply for a new H4 visa prior to returning as she will then no longer be in L2 status. This is the same scenario if she waits in the US until it is approved as she will need a new valid visa upon return from travel to India. She should also travel with a copy of the receipt notice to show a timely change of status petition has been filed if she returns prior to approval.

She will abandon her change of status request. She would have to wait for approval of your H-1B and apply for H-4 visa in order to obtain H-4 status. If you are still in L status at time of her returning she can enter on L visa provided it is still valid and would have to file new change of status request.