Generally speaking your stroller will need to be checked in as luggage. Some airlines and airports allow you to take your stroller to the gate. They will then place it in the plane’s hold (cargo area).Ask about gate delivery - this is where ground staff retrieve your stroller from the hold and bring it to you at the gate. This is generally only available on international flights. We have used this service at Tokyo (Narita), Paris - Charles de Gaulle and Sydney-Kingsford Smith airports with no problems.
You often have to walk for a long distance inside the airport terminal before you reach immigration and the baggage carousels so having your stroller with you helps enormously, particularly if you have an older baby or toddler or you have a lot of cabin luggage with you. Even if you end up carrying your baby you can still use the stroller to carry your hand luggage.
For most international flights you will have at least half an hour to an hour before you can board the plane. We always take a baby carrier such as our trusty Baby Björn with us, just in case we are forced to leave our stroller at check-in.
TIP - If you are able to take your stroller to the gate then it will need to pass through the security gates and will be searched. Your baby will also need to be taken out of the stroller and carried through the security gates - even if they are asleep. Make sure you don’t have too much junk stored in the storage sections of your stroller to make it easier at the security checks.
TIP - If you are like me then you will probably have foodstuffs like biscuits (cookies) or even fruit stashed in the pockets of your stroller. Remember to empty these before you pass through customs (or better still, before you check in your stroller) to avoid any fines for breaking quarantine regulations - this applies even between states in Australia!