Kanye West's Birthday -- Parties with Rap Gods ... But Where's Kim Kardashian?

Kanye West celebrated his 36th birthday last night in New York City with the likes of Jay-Z and Nas -- but some sites are calling out the fact that Kim wasn't there ... but that's just plain crazy.

West is the headliner for tonight's Governors Ball in NYC, so he had to be on the right coast for his birthday. Kim -- who is roughly 100 months pregnant -- is in Los Angeles and cannot travel for health reasons ... so clearly she could not be there.

But while we're here, let's discuss more important things ...