If you have a Yoyo style stroller, you can bring it to the gate and even on board. For more information, click here.
For other types of strollers, it depends on your departure airport.
In Paris Orly, Reunion Island, New York, and San Francisco:
The stroller must be checked in at the counter. It will be stored in the hold and returned upon arrival.
You can bring the stroller to the boarding gate.