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).