I'd agree for bipolar... For MOSFET H-bridges all-n-channel is common however, but special circuitry is in place to generate gate voltages
higher than the supply for the top MOSFETS.
Here's a bipolar H-bridge suggestion:
The middle resistors (R5 and R6) are used to set the maximum base current to the switch transistors,
so their value depends on the supply voltage and desired output current (and current gain of the
This actual circuit I've used with surface mount NPN/PNP superbeta transistor pairs for the switches, which
have very low Vsat, and a clever trick of using a small surface mount bridge rectifier to provide all 4
free-wheeling diodes in one go.
You must be careful not to drive both inputs high at the same time! Some means of monitoring over-current
would be a wise addition.