jQuery, Match and RegEx

So I have the following code in jQuery, and I am trying to essentially match dates in the format MM/YYYY where MM is a value between 1 and 12 and YYYY is a date in 1900s or 2000s. I haven't really used the jQuery test function before. Can someone tell me whats wrong with my code or the Regex?

        var fieldValue = $(this).val();
        if(!fieldValue.test(([1-9]|1[0-2])/^(19|20)\d\d)){
            Errors = Errors + 1;
            $(this).addClass("form_error");             
        }