The packing instructions of prams vary depending on the airline. You can check the guidelines of your airline in advance by contacting them or at the latest at the check-in.
Prams that will be checked in should be packed in a protective bag that can be either free or subject to a charge depending on the airline.
If you have to check in your pram, don’t worry. At Helsinki Airport, little passengers have the opportunity to continue their journey at the terminal in the airport's pram that you can find after the security control.