From Teletraan I: The Transformers Wiki

A stasis pod is used to store a Transformer protoform newborn until it has its spark installed, is given programming, and is formatted into a functional adult Transformer. The protoform is sealed safely inside the stasis pod, supported by nothing more than a lubricating fluid. In normal use, an exploration ship will carry several stasis pods, seed a planet with them, and the stasis pods would scan for native forms and birth new Transformer life.

Additionally, some of such a vessel's stasis pods will house "blank" protoforms, which are lifeless and do not contain sparks. One such blank protoform was used by Rhinox to restore Optimus Primal to life; Megatron used another blank to create Dinobot 2. These blank protoforms may be brought along to serve as backup bodies in this manner, or they might result when a stasis pod is damaged and the spark or datatrax of a "live" protoform are lost.

Because a stasis pod's life support functions are so efficient, they can also be used to transport adult Transformers, usually for long-distance travel. They have also been used to carry sentenced criminals into exile. (For example, the Axalon carried the murderous Protoform X and the thief Packrat.)