18 Weeks Pregnant: Symptoms & Baby Development - Babylist
18 Weeks Pregnant
June 7, 2022

18 Weeks Pregnant

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18 Weeks Pregnant.
18 Weeks Pregnant

How Big is Your Baby at 18 Weeks?

At 18 weeks pregnant, your baby is 5.6 inches long and weighs 6.70 ounces. That’s about the size of a Nintendo NES Classic Controller.

Here’s what else to know when you’re 18 weeks pregnant:

Your Baby at 18 Weeks

Big things are happening with your baby’s development this week, from hearing to nervous system. Find out more about what’s happening at 18 weeks.

Your Baby’s Development

  • Hearing: Baby can hear! Your beating heart is the loudest sound they hear. 💕 By week 25, they’ll be responding to particular voices.
  • Gender: When you have your ultrasound (it usually happens between 16 weeks and 20 weeks), the tech can tell you if you’re having a boy or a girl. The accuracy of this is really dependent on baby’s position, so maybe have a backup baby name. If it’s a girl, their fallopian tubes and uterus are now where they need to be. If it’s a boy, their little parts are (usually) visible on an ultrasound.
  • Nervous system: Your baby’s nerves are starting to develop myelin, a fatty substance that insulates them. This fancy process is called “myelination.” It’s a mouthful, but the gist is that it protects nerve cells and speeds up communication between them. This is super important in baby’s developing brain. Studies suggest that nutrition may help with healthy brain development—specifically, iron, choline and folate. So keep munching on leafy greens, eggs, beans and other nutrient-rich foods and take your prenatal vitamins to help boost baby’s brain power.

💛 Congratulations 💛

You are 45% of your way through your pregnancy.

18 Weeks Pregnant Ultrasound


Your Body: 18 Weeks Pregnancy Symptoms

While you may be feeling more energetic in the second trimester, you may find yourself dealing with new issues as you and your baby get bigger. Think Braxton Hicks contractions, round ligament pain and feeling off-balance (literally). Here’s what may be happening this week.

  • Weight: By this point most women are gaining around a pound a week. Since a baby weighs seven to eight pounds at birth, where is it all going? Well, two pounds is placenta and four pounds is blood, but here’s a full breakdown.
  • Balance: With all this extra mass, your center of gravity will change. You might find yourself tripping more than usual as your balance catches up, so remember to slow down. This can also cause back pain, but keeping your feet elevated will calm this.
  • Dry eyes: Pregnancy can dry out your eyes, which is especially irritating if you wear contacts. Try some preservative-free artificial tear drops that do not have cyclosporine (this helps treat dry eye, but there’s not enough data around if it’s safe or not to use during pregnancy or while breastfeeding).
  • Aches and pains: They’re normal during pregnancy, but around week 18, you might find some super uncomfortable feelings in your lower abdomen. Round ligament pain may be to blame. These annoying pains are caused by all the growing your baby is doing, which stretches the (yep) round ligaments and pulls at some pretty sensitive nerves in the groin. There’s not much you can do for this except stretch, switch positions and take acetaminophen (Tylenol), if your doctor gives the OK. Of course, aches and pains in the belly can be for other reasons, too, so let your OB know if you’re concerned, or if you have other symptoms, like bleeding, fever, chills or painful urination, or if the pain is severe.
  • Blood pressure: Wondering why your healthcare provider checks your blood pressure at every visit? Low blood pressure can cause lightheadedness and dizziness, like if you stand up too quickly. Usually this is considered normal and will go away after your baby’s born. On the flip side, high blood pressure can lead to problems including preterm birth and issues with the placenta, as well as preeclampsia, which can be dangerous for mom and baby. Know if you do have high blood pressure, you and your baby will be monitored closely.

Get Ready for Your 20-Week Ultrasound

You’re probably gearing up for the mid-pregnancy ultrasound—a.k.a. the anatomy scan, which happens around 20 weeks pregnant. And it really is just that. Baby’s whole body will be checked out to make sure development and growth are on track.

The highlight for many parents-to-be is finding out baby’s sex, but you’ll probably find it really amazing to see everything, from baby’s brain, to the heart and to those teeny little fingers and toes. If baby kicks while they’re on camera, you’ll see what those baby movements look like as you feel them.

Your due date will be confirmed based on baby’s size too. There’s a small possibility the date could change (despite what that due date calculator told you). But only around five percent of babies are born on their due dates, so it’s not set in stone.

Fun Fact

Your body is making 50% more blood than when you’re not pregnant to nourish the baby.

Your Life at 18 Weeks Pregnant

Even if you have plenty of second trimester energy, be gentle with your body and mind. These tips should help.

  • Top tip: Struggling to sleep? Who can blame you. You’re not supposed to sleep on your back anymore, belly sleeping is definitely out and your bladder feels about the size of a pea. But don’t give up hope for a good night’s sleep. Here are seven tips to help, plus some tips on the best sleeping positions.
  • Recipes to try: When lots of snacking is required, it’s easy to fall into a carb-heavy rut. But also try to get the ruffage your gut needs with daily servings of fruits and vegetables. Not only does fiber help with constipation, but you’ll also expose your baby to a wide variety of vitamins and minerals. These veggie-based dishes work for both lunch or dinner: Kale and Brussels Sprout Salad, Roasted Cauliflower Soup and 5-Ingredient Summer Squash Pizza.
  • Good gear: An exercise ball will be your best friend as your belly grows. You can use it in lieu of a desk chair for core strength and lower back support, as a tool for prenatal workouts that encourage pelvic stability (Google has a lot of videos) and as a birth ball during labor. Major bonus: You can use it later to bounce your baby to sleep.
  • Books we love: Now is a great time to tuck into that super-long book you’ve been meaning to read. Not only will it help to pass the time, but once your baby is in the house, it could be awhile before a 500-plus page book sounds realistic. Need a recommendation? Check out the Neopoltian novels, The Goldfinch or The Amazing Adventures of Kavalier and Clay.

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 18 Weeks Pregnant Belly

Expected weight gain is about 1 pound per week in the second trimester. At your first prenatal appointment, your healthcare provider probably gave you a weight gain range to try to stay within, based on your BMI (body mass index). It may be tough to stay on track—and it’s kinda no fun getting on a scale so often—but OBs say slow and steady weight gain is important for your and your baby’s health.

At 18 weeks, some pregnant bellies look, well, pregnant, and other women are just starting to show. You may be feeling baby’s movements on the regular or might just start to feel a flutter or two. Pretty soon those kicks will be unmistakable.

18 Weeks Baby Bumps from Real Moms

18 weeks pregnant belly @cparran fitmom

18 weeks pregnant bump @gracechalgren

18 weeks pregnant belly pictures @mrslampkin1908

18 weeks pregnant belly size @gheeful

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18 weeks pregnant pictures @jayceegatwood

18 weeks pregnant woman @notasouthernbell

pictures of pregnant belly at 18 weeks @ruufiooo

18 weeks pregnant belly @colormekenna

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18 Weeks Pregnant Checklist

  • Since baby can hear now, consider making a baby Spotify playlist of some of your favorite songs or tunes that are soothing, like classical music.
  • Make sleep a priority. Consider buying a pregnancy pillow and experiment with a regular bedtime if you don’t already have one.
  • As your belly starts to show, it’s a good time to coach older siblings-to-be about the baby joining the family.
  • Brainstorm baby names. Right now, anything goes! Fun places for inspiration: Family names, places, nature and religion/spirituality.
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