At 31 weeks your baby is approximately 16 inches from head to toe, and weighs approximately 3 1/3 pounds(about the size of a coconut).
Your baby is quickly approaching its birth length — though it’ll likely pack on another three to five pounds before baby’s due date. Baby's also putting in longer stretches of sleep, which is why you're probably noticing more defined patterns of wakefulness(movement) and rest(when baby's pretty still). Your baby's organs are continuing to mature and baby is passing water from its bladder: good practice for the urinating it'll do after it's born. Your baby's brain is working overtime these days, developing faster than ever. Connections between individual nerve cells (baby's got to make trillions of them!) are being made at a super fast rate. It's now processing information, tracking light and perceiving signals from all five senses. Sure, your baby can't smell anything right now, but that's only because it's still submerged in amniotic fluid and needs to be breathing air to get a whiff of anything. Lucky for you — and your baby — yours will be one of the very first scents it breathes in, a scent that will quickly become its very favorite. This week also boasts some exciting reproductive developments. Having a boy? His testicles are moving through the groin on their way into the scrotum. And if you've got a girl in there, her clitoris is already relatively formed.
Note: Every baby develops a little differently — even in the womb. This information is to give you a general idea of your baby's size.
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