New to certification, the following are recommended:
Exam 461: Querying Microsoft SQL Server 2012
Exam 462: Administering a Microsoft SQL Server 2012 Database?Part1
Exam 463: Implementing Data Warehouses with Microsoft SQL Server 2012?Part 2
You just need to upgrade your certification, then MS recommends the following:
Any MCTS on SQL Server 2008
Exam 457: Transition your MCTS on SQL Server 2008 part 1
Exam 458: Transition your MCTS on SQL Server 2008 part 2
Source: http://www.microsoft.com/learning/en/us/certification/cert-sql-server-mcsa.aspx