I think that depends where the axle bends. I have fished a couple baby joggers out of the dumpster, and they had bent axles; but the axles bent right where they were attached to the dropout, so it didn't bother the alignment between the bearings.

I'd check how much weight the baby jogger was supposed to be able to carry; as long as you don't go too much over that, you should be fine.

If they do bend, you can probably straighten them; but if you do, replace them ASAP. Bending means metal fatigue, and each successive bend will be worse, until it breaks.