My guesses for the sexes are in order:
1: 1 boy 1 girl
2: 2 boys
3: 2 girls
I think now is the time to take a stand on your guess!
My first and second guesses are pretty close on my guess scale but #3 of 2 girls seems very unlikely in my mind. Why? I don't know. I'm just so excited I can't hardly wait- I've been anticipating it for like 7 weeks since the appointment was made!! Any combination sounds just absolutely wonderful and exciting to me!
Here is a copy and paste of their development now:
Your baby weighs about 10 1/2 ounces now. He's also around 6 1/2 inches long from head to bottom and about 10 inches from head to heel — the length of a banana. (For the first 20 weeks, when a baby's legs are curled up against his torso and hard to measure, measurements are taken from the top of his head to his bottom — the "crown to rump" measurement. After 20 weeks, he's measured from head to toe.)
He's swallowing more these days, which is good practice for his digestive system. He's also producing meconium, a black, sticky by-product of digestion. This gooey substance will accumulate in his bowels, and you'll see it in his first soiled diaper (some babies pass meconium in the womb or during delivery).
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Fraternal Twins in the womb at 20 weeks. This is from the same website that the 16 week picture is from.
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20 weeks!
19 weeks (not a whole lot of difference!)