At 16 weeks, you're officially 4 months pregnant!
As your second trimester hums along, your baby's growing rapidly, and you might start seeing changes to your own body, too — so if you haven't already gone shopping for maternity clothes, now's the time.
Your Baby at Week 16
What’s going on inside your ever-expanding belly this week? For one thing, your little boxer is working up to fighting weight. Sure, her body still looks pretty thin and fragile — especially with only a translucent layer of skin covering those blood vessels and bones. And yes, she’s only four to five inches long and weighs just three ounces. But your little flyweight is starting to gain some muscle mass. Her back muscles are getting stronger, enabling her to straighten her head and neck even more. Stronger muscles also allow her to make some of her very first facial expressions. Was that a grin?
Talking about that getting-more-adorable-by-the-day face, your baby’s eyes are facing fully forward and framed by a fringe of eyelashes and tiny eyebrows. And though her eyelids are still sealed shut and will stay that way for another ten weeks or so, those tiny orbs will soon be able to perceive light…even though there’s nothing to see. It’s always dark, after all, in baby’s hotel womb.
In other news, your little one’s ticker is pumping around 25 quarts of blood per day through her growing body. That sounds like a lot of pumping action going on, but it’s only the beginning. By the time your baby is ready for her debut, her heart will be pumping 1,900 quarts a day!
At a Glance
16 weeks pregnant is how many months?
If you're 16 weeks pregnant, you're in month 4 of your pregnancy. Only 5 months left to go! Still have questions? Here's some more information on how weeks, months and trimesters are broken down in pregnancy.
How big is my baby at 16 weeks?
Your baby now weighs in at a whopping 3 to 4 ounces and is 4 to 5 inches in length.
The backbone and tiny muscles in your baby's back are gaining strength, so she can straighten out that head and neck even more.
Baby's eyes are working
Thanks to those developing facial muscles, your baby is capable of making a few expressive frowns and squints, even at this early stage.
Baby's beautiful eyes are finally working too, making small side-to-side movements and perceiving light, although the eyelids are still sealed. Peekaboo!
Baby's skin is transparent
Your fetus is becoming a looker too — with a face that's starting to look more human — but a skinny looker, since there's no baby fat yet.
And here's the skinny on baby skin: It's practically translucent now, so if you took a peek inside your uterus, you'd be able to see your baby's blood vessels under that thin skin.
Baby will soon hear your voice
Listen up: Tiny bones in your fetus' ears are in place, making it likely that baby will soon be able to hear your voice (or something like it) when you're speaking. Generally, babies fully develop the ability to hear in the womb by 18 weeks of pregnancy.
In fact, studies have found that babies who hear a song while they're in the womb recognize the same tune when it's sung to them after they’re born — so choose your lullabies with that in mind.
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