20 Weeks
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).
21 Weeks.
How your baby's growing:
Your baby now weighs about three-quarters of a pound and is approximately 10 1/2 inches long — the length of a carrot. You may soon feel like she's practicing martial arts as her initial fluttering movements turn into full-fledged kicks and nudges. You may also discover a pattern to her activity as you get to know her better. In other developments, your baby's eyebrows and lids are present now, and if you're having a girl, her vagina has begun to form as well.22 Weeks