Interesting since Argonian children were referred to as hatchlings before...which would suggest they come from eggs. Who knows though, except Bethesda who writes it.
There is still an egg, it just does not hatch outside the body. That term still holds true.
However, it is confirmed:
Pete Hines
Do Argonians lay eggs? (11/06/03)
Argonians are ovoviviparous. [Wow. I was SURE I'd never have to use that word again.] They don't lay eggs like reptiles.
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