Navigating a crowded airport with a young child is a tricky task made quicker when she's seated in a stroller. Navigating a crowded plane aisle, however, is a different story. Most airlines will allow you to check a stroller either at the ticketing counter or at the gate, but be sure to check your airline's policies before you leave home.
Strolling Through Airport Security
The Transportation Security Administration requires travelers to submit strollers for X-rays during screening. Agents will ask you to collapse your stroller so it can be placed on the belt of the X-ray machine. You'll then need to carry your child through the metal detector or body scanner used to screen passengers. If your stroller can't be collapsed enough to pass through the X-ray machine, agents will have to inspect it by hand.
Boarding the Plane
Many airlines allow you to check a folded stroller without paying baggage fees, provided you're traveling with a small child. If you take the stroller to the gate, ask an agent to gate-check it. You'll leave the stroller outside the plane door and retrieve it in the same spot upon landing. Note that airline policies vary slightly. For instance, American Airlines requires strollers weighing more than 20 pounds to be checked at the ticket counter, while allowing lightweight umbrella strollers to be taken on board and stowed in overhead compartments. Check your airline's specific policy ahead of time.