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16 Weeks Pregnant: Baby Update

This week, the bones deep in the ear that allow your baby to hear sounds—like your voice—are now formed. Right now, everything is pretty muffled in there. But, by their first day of life, your little one will be so attuned to your voice that they will be able to recognize you singing over someone unfamiliar.

Their intestines are starting to produce meconium, the tarry, black-green-colored poop babies pass during the first few days of life.

And while their face is almost fully developed, they're only beginning to layer on the baby fat that’ll protect them from temperature changes and give them energy after birth.

How Many Months is 16 Weeks Pregnant?

16 weeks pregnant is nearly 4 months pregnant. 

Baby’s Size at 16 Weeks Pregnant

At 16 weeks, your baby is the size of an avocado. 

16 Weeks Pregnant: What to Expect

Did you just feel something? Your baby’s first little kicks started months ago, but around this time you can definitely feel them. Doctors call these flutters “the quickening.” And it is often an astonishing and surreal feeling!

Watching your belly grow is exciting! Seeing stretch marks pop up might not be. Stretch marks usually begin to appear in the second trimester and up to 90% of pregnant people get them. They first look like thin red or purplish lines. Those are little cracks in the dermis, the middle layer of your skin…under the epidermis. Stretch marks often start on the underside of the belly, but may also occur on the breasts, hips, upper legs and behind.

Stretch marks happen when your skin stretches too fast. Can you prevent them? No one knows for sure. Some nutritionists recommend collagen-rich foods, such as bone broth, as well as zinc, vitamin C and plenty of water to keep your skin firm and hydrated. Some people swear by moisturizing creams, but doctors are not convinced. Applying oils or balms can’t hurt and they sometimes ease the itching that can come with all that stretching.

Bottom line: Stretch marks are totally normal and many parents have tiger stripes! But, there are some post-pregnancy options for trying to reduce them, if that’s what you decide to do. Treatments range from topical creams, microdermabrasion and peels to pulsed-dye laser therapy and micro-needling.

16 Weeks Pregnant To-Do List

  • Take a hospital tour: If you plan to give birth in a hospital, make sure to schedule a private tour of the facilities. Bring along a list of questions. You may want to know things like:

    • Where will I be examined when I arrive?
    • What is your C-section rate?
    • How many people will be allowed in the room with me as I birth?
    • Can I move around while in labor?
    • Can I eat and drink while in labor?
    • Is there a separate baby nursery?
    • Are private rooms available?
    • Can I labor or birth in water?
    • Is there a NICU?
    • What sort of breastfeeding assistance do you offer?
    • What is the hospital’s attitude towards natural birth?

  • Begin a baby registry: If this is your first baby, you’re probably starting from square one. It can feel like there are a thousand things to buy, from the small (burp cloths) to the big (stroller). Draft a list divided by task: sleeping, eating, diapering, bathing, and transporting the baby. Then add in the fun stuff like clothes, toys, mobiles, and more. Think about adding SNOO Smart Sleeper, which gives babies a safe place to sleep and has been shown to add an hour of sleep a night on average! (Learn about creating a Happiest Baby Registry.) 

  • Get some sunshine: Just 10 to 20 minutes of sun a day can help improve your mood and your baby’s health.

Pregnancy Myth or Fact: Should you avoid ab exercises during pregnancy?

No—it's a myth that you should skip ab exercises. Strengthening your abs before and during pregnancy can help with lower back pain and lead to a quicker recovery post-pregnancy. Conventional crunches are out when you’re pregnant and while you’re healing afterward (they can worsen diastasis recti, that’s when your abs muscles pull apart a bit down the middle, causing a little, middle-of-the-belly “pooch”). However, exercises like plank position and a side plank are good ways to tone your core during your first and second trimester. Check out these pregnancy-safe exercises!  

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About Dr. Harvey Karp

Dr. Harvey Karp, one of America’s most trusted pediatricians, is the founder of Happiest Baby and the inventor of the groundbreaking SNOO Smart Sleeper. After years of treating patients in Los Angeles, Dr. Karp vaulted to global prominence with the release of the bestselling Happiest Baby on the Block and Happiest Toddler on the Block. His celebrated books and videos have since become standard pediatric practice, translated into more than 20 languages and have helped millions of parents. Dr. Karp’s landmark methods, including the 5 S’s for soothing babies, guide parents to understand and nurture their children and relieve stressful issues, like new-parent exhaustion, infant crying, and toddler tantrums.

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Disclaimer: The information on our site is NOT medical advice for any specific person or condition. It is only meant as general information. If you have any medical questions and concerns about your child or yourself, please contact your health provider.