It’s a couple weeks early, but what the hey. Some of these ladies may not be pregnant two weeks from now. 
The fetus holding the tiny trick or treat bucket is so cute. 
Actually all the costumes are very imaginative.
What did the fetus say to its pregnant host on Halloween? I want my mummy. he he
Cute! My sister went as a pregnant nun, with her husband as a demonic priest. I was the fallen sister; carried a Playgirl around and drank and smoked, lol.
On a flip note, my mom dragged 3 of us around with a pillow stuffed to make it look like she was pregnant; we named the pillow Penelope, and sure enough, 6 years later when my sister was born, we all wanted to name her Penelope. (She lucked out and my mom said NO, lol)
The best one I’ve seen was a zombie hand & arm, complete with some bone showing, clawing it’s way out of it’s zombie mother.
My wife is six months along and plans to go as the Eye of Sauron.
See, now this makes perfect sense. She’s a chip off the ol’ block.
My sister dressed up as a “vestal virgin”, white diaphanous gown with gold cord ties just above her ginormous 8-month pregnancy. Hilarious.
People who ran into her later on at the con were surprised to see that she really was pregnant. 
I was gonna say, “a great big eye…”
While 8 months pregnant with my brother, my mom wore a wedding dress and carried a shot gun.
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Wait for it…
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She was a “shotgun wedding”!!
The wrap party for the Simpsons’ first season was held in a bowling alley. Nancy Cartwright (voice of Bart and some others) was nine months pregnant at the time. She had a friend make her a white jumpsuit with a red line around her baby bump.
She was a bowling pin!
I went as a deviled egg when I was pregnant. I think I stole the idea from someone on this board actually.
White shirt with a yellow felt circle glued to the belly section. Devil horns and a tail. So easy and I won second place in the costume contest at the party I went to.