21 Weeks Pregnant: Symptoms & Baby Development - Babylist
21 Weeks Pregnant
April 6, 2021

21 Weeks Pregnant

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21 Weeks Pregnant.
21 Weeks Pregnant

How Big is Your Baby at 21 Weeks?

Your baby is 10.5 inches long and now weighs a little over 12 ounces (about 3/4 of a pound). That’s about the size of a My Little Pony.

Here’s what else to know when you’re 21 weeks pregnant:

Your Baby’s Development at 21 Weeks

You know your baby is growing fast, but how do you explain the big jump in inches? Baby’s being measured differently now. See what else is happening this week.

  • Baby size: How did your baby jump from 6.5 inches to 10.5 inches in one week? Baby’s growth isn’t that crazy—it’s just being measured differently now. This week, the measurement changes from butt to head (aka crown to rump) to head to toe (aka crown to heel). Your growing baby is finally starting to stretch out their legs, so they can be more accurately measured in ultrasounds.
  • Reproductive system: It may seem premature, but your baby is developing their ability to have babies. Pretty meta, huh? Males are developing their testes, while females are developing their ovaries and all of the eggs they will have in their life—about a million.
  • Eyelids: In other fetal development news, your baby’s eyelids are developing this week, but it’ll take a while longer before they nail a cute wink. 😉
  • Baby moving: This week, if you were to push on your belly, your baby would shimmy out of the way because their skin now responds to touch.

21 Weeks Pregnant Fetal Movement

As your baby grows, you’ll feel them moving more and more. What starts to feel like a butterfly flutter around weeks 18 to 20 will develop into cute kicks and jabs—and then (brace yourself) full-on dancing on your bladder in the third trimester.

You might notice that baby isn’t always cooperative when it comes to when they move. You may find your baby is still while you’re up and walking around, and then when it’s time for you to rest, baby moves around like crazy. Consider this prep for the future—newborns are on their very own schedules, and we’re the ones who need to adapt to them.

21 Weeks Pregnant Ultrasound


💛 Congratulations 💛

There are 133 days until your due date!

Your Body: Pregnancy Symptoms at 21 Weeks

Now that you’re a little over halfway into your pregnancy, you may be noticing fun side effects, like strong nails and lush hair. On the flip side, you may find yourself dealing with heartburn or other physical discomforts. Here’s what may be happening with you this week.

  • Killer nails: Extra estrogen during pregnancy can make your hair and nails grow faster. Now’s the time to get that mani/pedi. Your hair has longer growth stages, too, so you’ll be shedding less.
  • Itchy skin: As your belly expands, you might start feeling dry and itchy. Avoid hot baths, and try a cool oatmeal bath or rub on some unscented lotion to help soothe the itch.
  • Heartburn and indigestion: All that expansion also puts extra pressure on your intestines and stomach, which can cause some unpleasant digestive symptoms. Avoid spicy and greasy foods, eat at least an hour before lying down and try to eat smaller meals—maybe five or six mini-meals instead of three big ones each day. Most OTC antacids are OK to take during pregnancy, but check with your healthcare provider first to be safe. Some pregnant women find that eating yogurt, drinking milk or mixing a spoonful of honey into warm milk helps ease heartburn. If your heartburn or indigestion get really bad or don’t ease up no matter what you do, talk with your doctor.
  • Leaking breasts: You might be surprised to find your breasts leaking while you’re pregnant. That liquid isn’t exactly breast milk. It’s colostrum—a thick, yellowish, nutrient-dense fluid that’ll be baby’s first food for a few days if you decide to breastfeed.
  • Braxton Hicks contractions: If you feel a tightening of your belly that goes away, you may be feeling these “fake” contractions. Braxton Hicks contractions at 21 weeks are normal. If they bother you, try drinking some water or changing positions. If they don’t go away or become more frequent, you should call your healthcare provider in case they’re actual labor contractions.

Fun Fact

Your baby can already taste what you’re eating!

Your Life at 21 Weeks Pregnant

Doulas, chiropractors and baby gear, oh my! There’s plenty to think about as the weeks progress, but we’ve narrowed down some specific topics to help you get started.

  • Doula 411: To doula or not to doula? It’s usually a question that arises sometime during the second half of your pregnancy. Doulas are trained and experienced in childbirth, but unlike midwives and doctors, they don’t actually deliver your baby. Instead, doulas are there to provide you whatever support you need during labor. They’ll often help you in your postpartum journey as well. You don’t have to make your decision today, but it can be helpful to start thinking about whether having a doula is something you want to pursue. You’ll need time to research local doulas in your area and build a relationship with whomever you choose.
  • Good for your bod: The American Pregnancy Association says that it’s estimated 50 to 70% of pregnant women will deal with back pain at some point. Chiropractic care or massage therapy can be hugely beneficial when it comes to treating and preventing both prenatal and postpartum back pain. Just make sure to look for someone specifically trained in prenatal or perinatal treatment.
  • Bare necessities: If you’ve spent any time researching baby stuff online, then you know the options are practically endless. Want a changing table that doubles as a scale? No problem. How about a cradle that rocks your baby to sleep for you? Done and done. Despite the cool-factor of these new products, you really don’t need much when it comes time to bring baby home from the hospital. If you’re more of a minimalist, forgo the gadgetry in favor of the true must-haves. Here’s our list of essential baby gear.
  • Book a maternity shoot (or don’t): If you want to schedule maternity photos, the best time to do so is usually between 30 to 36 weeks. Use the next few weeks to find and price-out nearby photographers. Not interested in a maternity shoot? That’s OK too!

To-Do: Create Your Babylist

With Babylist, you can add any item from any store onto ONE registry. You’ll even get a Hello Baby Box full of free (amazing!) goodies.

Your 21 Weeks Pregnant Belly

At 21 weeks pregnant, weight gain should continue at around a pound per week. Your pregnant belly is getting rapidly bigger—now you may be able to feel the top of your uterus with your fingers about a half-inch above your belly button.

At your OB appointments now, they might start measuring your fundal height—the distance between the pubic bone and the top of your uterus. It helps keep tabs on baby’s growth and amniotic fluid level.

21 Week Baby Bumps from Real Moms









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21 Weeks Pregnant Checklist

  • Pick a carrier to add to your registry.
  • Finalize your baby shower guest list and send it to your host.
  • If you want maternity snaps, pick a photographer and schedule your photoshoot for the middle of the third trimester.
  • Celebrate that you are more than halfway done. You’ve got this!
This information is provided for educational and entertainment purposes only. We do not accept any responsibility for any liability, loss or risk, personal or otherwise, incurred as a consequence, directly or indirectly, from any information or advice contained here. Babylist may earn compensation from affiliate links in this content. Learn more about how we write Babylist content and the Babylist Health Advisory Board.