On 3rd December 2012, St James's Palace announced that the Duchess was pregnant and expecting her first child. The royal baby and heir to the throne is due to be born in July 2013.
http://www.examiner.com/article/when-is-kate-middleton-due-5-hints-at-a-july-2013-royal-baby
http://www.examiner.com/article/when-is-kate-middleton-due-5-hints-at-a-july-2013-royal-baby