Is it possible to receive an egg from a Pokestop when your bag is at or above its capacity, but there is room for additional eggs?
I tried this 6 or 7 times today while I only had 5 eggs, and did not get any, but this could have just been bad luck.
From my own personal experience you cannot receives eggs from pokestops if your item inventory is full even if you have less than 9 eggs in your pokemon inventory. Some cursory searching doesn't show anyone who has been able to receive eggs when inventory is full.
Source: Personal experience and here
From personal experience with the game, if I have 9 eggs in my bag, I cannot receive any more eggs. I don't know if this is documented anywhere, but from playing the game with a full bag of eggs now, I haven't received any new eggs. I doubt it's just bad luck.
From my personal experience you cannot receive any eggs with a full bag. I live near the city so I'm able to get the pokestops and after nearly 15 poke stops with a full bag I was not able to get any eggs!