Jody Craddock's controversial equaliser rescued a point for Wolves and put a dent in Birmingham's promotion hopes.
Referee Mark Halsey waved play on after Gary Breen's apparent foul on Sebastian Larsson and Craddock went on to meet Jay Bothroyd's flick to secure a point.
It ended a run of five away defeats for Wolves, who were also indebted to a string of saves from Matt Murray.
Gary McSheffrey's rising drive gave the hosts the lead, while Fabrice Muamba also went close before Craddock's goal.
Birmingham boss Steve Bruce on the head injury to Sebastian Larsson:
"I spoke to the referee (Mark Halsey) and said that usually with a head injury the game is stopped.
"He said he didn't think Larsson had a head injury. That's why he's rolling on the floor with his head in his hands!"
Wolves boss Mick McCarthy:
"I am delighted to have come here and picked up the point. Birmingham had won five games on the trot and it was a great result for us.
"They had the better chances and our goalkeeper Matt Murray was excellent.
"But we have stuck to our task and had the better of the second half when we silenced the home crowd."
Birmingham: Maik Taylor, Kelly, Jaidi, Martin Taylor, Sadler,
Larsson, Muamba (Nafti 73), Clemence, McSheffrey,
Jerome (Danns 73), Bendtner.
Subs Not Used: Doyle, Campbell, Kilkenny.
Goals: McSheffrey 30.
Wolverhampton: Murray, Little, Breen, Craddock,
Mulgrew (Edwards 34), Gobern, Olofinjana, Potter (Johnson 80),
Henry, Jones (Ricketts 71), Bothroyd.
Subs Not Used: Ikeme, Craig Davies.
Goals: Craddock 89.
Att: 22,256.
Ref: M Halsey (Lancashire).