Cox, 23, has made 17 appearances for Albion this season and scored three goals, which came in the Carling Cup.
Ipswich manager Paul Jewell has turned to Cox, who cost ?1.5million from Swindon in July 2009, after failing with a loan move for 20-year-old Aston Villa striker Nathan Delfouneso.
On his way: Cox (left) has fallen down the pecking order at Albion
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Explore more:People: Simon Cox, Paul Jewell