But the on-loan Chelsea centre back made amends when he equalised seven minutes after the break before Yakou Meite's 12th goal of the season in the 56th minute then substitute Judilson Gomes sealed victory for Mark Bowen's side three minutes from time.
Birmingham were good value for their early lead. Hogan showed a real poacher's instinct to send a looping header over goalkeeper Rafael Cabral after latching on to Miazga's poor back header from Marc Roberts's long ball forward.
Hogan was guilty of a huge miss in the 17th minute, blazing over at the far post from Jutkiewicz's cross.
Ivan Sunjic then fired a rising, angled effort into the sidenetting from Hogan's pass as Blues remained on the offensive.
But Reading forced the first save, in the 25th minute when Royals right back Andy Yiadom dispossessed Blues left back Kristian Pedersen and fed Meite, whose left foot shot was beaten away by goalkeeper Lee Camp.
Birmingham had the better of the rest of the half but were wayward with their chances.
Jutkiewicz glanced well wide before Hogan sent an overhead kick comfortably over the bar.
Shortly after half-time, Blues missed another chance to have made it 2-0, when the unmarked Jutkiewicz got too much on his header from Bellingham's free kick and the ball floated harmlessly over the bar.
Reading made Blues pay by equalising three minutes later.
Miazga met Andy Rinomhota's right-wing cross full on the volley from 10 yards, giving goalkeeper Lee Camp no chance in the Blues goal for his second goal of the season.
Reading turned the game on its head by taking the lead shortly before the hour mark.
Meite got across Pedersen to meet John Swift's deep free kick to glance home a powerful downward header from seven yards out.
Gardner forced Cabral into routine saves from his 25-yard drive then a glancing header.
But Reading hit Blues on the break with a third goal as Gomes raced away on the counter-attack before coolly curling low past Camp.