Adding items to DDL

[Vik]

There are a few dropdown lists on an .aspx page. A user can open a popup
window and add the new items to the DDLs on the main page. The new items are
added using JavaScript, so the main page is not reloaded. At the same time
the new items are also saved in a database.
When the new item is selected in the DDL on the main page and the page is
posted back, the DDL does not contain the new items and its Selected Index =
0.
I think I can add a hidden field on the main page for every DDL and save the
selected values from the DDLs in these fields using JavaScript.

Is there a better solution?

Thank you.