Do eggs expire in Pokémon Go?

I've been holding on to some eggs, waiting to get an incubator at level 25. I thought I was sitting on two 10 km eggs. When I finally reached level 25, I noticed I only had one 10 km egg.

Was I mistaken about my eggs, or do eggs expire?

Solution 1:

Eggs do not expire. Once you have 9 eggs, they will remain until one of them hatches through an incubator. Only then can you get a new one.

I'm guessing either:

• you hatched the egg and maybe don't remember hatching it since you got a new one (I personally don't always notice when I get a new one through pokestops if I get many objects during at that pokestop).
• There is a glitch and the 10km one got replaced?

However there is probably no fix for this, you're stuck with the eggs you have until you hatch them.

To answer your question: no, eggs don't expire.