The offspring would be born in a caul.

@Blood Brandy  
You’re making it really hard to be logical right now XD

@Trixie1995  
Magic?

@Jryvn  
That’s specific for platypuses only though… And she’s neither a platypus nor a bird, shes a pony… Those are kinda exclusive to those mammals. I really don’t see how a pony could just acquire new genetics to birth with eggs unless they specifically tested with her prior before she was born.

@Trixie1995  
Birds are warm-blooded and platypuses can lay eggs.

@Trixie1995  
Difficult to say because often times, Dragons are able to impregnate anything that moves, and sometimes, things that don’t

Less than likely would be able to have children period. BUT if it was possible, the mother is obviously the one who houses the baby(which is warmblooded and therefore cannot produce eggs with shells even if she wanted to.), therefore I think she will not have an egg, but in fact maybe a dragon without scales and one with a bellybutton. Or, it could just wind up causing complications for rarity and thus possibly killing her all together. shrugs

Maybe she won’t be pregnant.

If it was a griffon, yes, but these are pegueas, it gonna be live birth.

@phoenixacezero  
Just based on the idea of avian characteristics being a contributing factor (I.E. If Spike hooked up with Gilda, maybe a pretty good chance of an egg)

@Blood Brandy  
Explain?

Maybe, but the chances of an egg would probably be better with Rainbow Dash or Fluttershy

No. Since the mother a unicorn, any rarity breeding with spike result in live birth.

It’s certainly an “eggselent” question.

Yes. Probably.
 
TRANSLATION: This is my headcanon.

@Background Pony #0D9C  
http://www.youtube.com/watch?v=iOz4zg5mZBk

Don’t some eggs have a soft shell that hardens when exposed to the air? If so, it could be like squeezing a tube of toothpaste.

Based on the show, for all we know, both “ponies” and dragons could be acelluar life-forms.

I think the better question is whether ponies and dragons even can have children together.

Seeing as they have magic for everything else in Equestria, I’m sure Twilight Sparkle could find the equivalent of the “Accomodation spell” from the Xanth novels.
 
(If you haven’t read them, the “Accomodation spell” allows two creatures of different species to have, er, “relations” with one another by temporarily transforming each creature into a hybrid between its species and the other’s. This happens a lot in the Xanth novels, which I think says a bit more about the author Piers Anthony that I’d care to speculate on.)

no, rarity would get arrested for pedophilia

I dunno.
 
I’m pretty sure since the baby is being made inside a mammal it would have a mammalian birth. Probably a little simplistic without going into any kind of differences between the uterus of a mammal and that of a reptile, but then again, Dragons are often depicted as being something of a long ago ancestor that predates such classifications and shows traits of Mammal and Reptile (Scales, Warm blood, etc.)
 
…Yeah I either need to stop thinking about this or start getting coherent and sciencey

MAMMALS DO NOT WORK THAT WAY!
 
GOOD NIGHT!

Oh U Guys :D

:)