Loanee N'Daw fell out of favour with previous Ipswich boss Paul Jewell but has been recalled to the centre of midfield alongside another loan signing, Richie Wellens.
McCarthy has also gone for loan keeper Stephen Henderson ahead of Scott Loach between the sticks.
Birmingham have won four of the last five league meetings against Town and are unbeaten in 12 at St. Andrews against the Suffolk side.
Birmingham: Butland; Robinson, Davies, Caldwell, Murphy; Redmond, Mullins, Morrison, Elliott; Lita, King
Ipswich: Henderson; Edwards, Chambers, Higginbotham, Cresswell; N'Daw, Wellens; Reo-Coker, Martin; Murphy, Campbell