What To Expect In Your Third Trimester Of Pregnancy

Picture of Robyn Rosenblum, MD, FAAP
woman in third trimester looking down at her belly

Regardless of how easy or difficult your pregnancy has been, by the third trimester you’re itching to meet your little one! But don’t wish them into this world too soon — they (and you!) still have some growing to do.

In this article, the Newton Baby experts tell you about some of the changes to expect during your third trimester and what you can do about them. We’ll also give you a third-trimester checklist so you can be sure that you’re ready for your baby to make their appearance!

But before we get to that, let’s talk about when the third trimester is and how your baby is growing.

When Is Your Third Trimester?

Let’s do a little review. Your first trimester begins on the first day of your last period and lasts through week 12. The second trimester includes weeks 13 through 27, and that brings you to the grand finale: the third trimester.

The third trimester begins week 28 and lasts until your little one decides to make their appearance, which is typically somewhere around 40 weeks.

Your baby may come a bit early or late, which is usually no problem. But if your baby is born too early or too late, they’ll be considered premature or overdue.

Babies are considered premature when they’re born earlier than three weeks before the due date or, in other words, before week 37.

On the other end of the spectrum, babies are overdue if you’re 42 weeks pregnant and still haven’t gone into labor.

Your Baby’s Growth During The Third Trimester

At the beginning of the third trimester, your baby only weighs around two or two and a half pounds. They’ll probably triple that weight by the time they’re born.

Your little one still has a lot of growing and developing to do before they’re ready to be in the real world!
The third trimester is when your baby will be able to fully open their sweet little eyes. Their toenails peek out around week 32. And, shortly after that, their pupils will begin responding to light.

They continue to mature and develop and bones continue to harden, though their skull will stay soft for delivery.

As your baby grows, you’ll feel them kick more and more. Then, around 34 weeks, babies typically turn so that their head is pointed down to prepare for birth.

If your baby doesn’t make that move on their own, your doctor may try to turn them around 37 weeks.

woman in third trimester getting an ultrasound

The Third Trimester: What To Expect And What To Do

With all the growing your little one has to do during this trimester, it makes sense that your belly and body will also go through some changes!

You will, of course, gain more pregnancy weight during these last few weeks, but there are some other changes you may experience in your body as well.
Let’s take a look at a few of the things you’ll notice and feel and what you can do

Aches And Pains

What To Expect

As your baby grows bigger by the day, so does your belly.

You may experience some discomfort, soreness, or pain in your back, pelvis, hips, and abdomen as your body prepares for labor and changes to accommodate the extra weight you’re carrying around.

What To Do

Figure out what works to ease your discomfort. Try a warm bath, a heating pad, or taking a walk.

You may also want to sleep on your side with a pillow between your legs. Protect your lower back (always bend at the knees to lift something!) and skip high heels until after you give birth.

Changes In Your Breasts

woman in third trimester pulling up her bra strap

What To Expect

You might have already gone up a cup size or two since you got pregnant, and you can expect a little more this trimester. Your nipples may also grow and change shape to prepare to feed your baby. 

You may even notice that you begin to leak colostrum, which is the first (and most nutrient-rich) milk that your little one will consume if you breastfeed.

What To Do

If you think your bra might not be the right fit, do some shopping for the correct size. You also might find it more comfortable to sleep in a soft sleep bra.

If you’ve started leaking colostrum, wear nursing pads to keep it from soaking your clothes.

Vaginal Discharge

What To Expect

It’s normal to experience more vaginal discharge the closer you get to delivery. However, certain types of discharge can be a cause for concern, so you’ll want to keep an eye out.

What To Do

If you notice a discharge that’s smelly, pink or red (which could indicate blood), or any color other than milky white, talk to your doctor. You’ll also want to call them if there’s a change in the amount, consistency, or color of the discharge.


woman lying in bed with newton baby's weighted blanket

What To Expect

Remember how tired you felt during your first trimester? Unfortunately, the fatigue and the urge to lie on the couch and nap often return in the third trimester.

What To Do

If you can, get in bed early or take time for naps! If nothing else, grab a magazine and lie on the couch for a bit. A few minutes with your feet up might make all the difference.

In addition to resting, eat well and try to stay active to keep your energy levels up.

Uterus Growth

What To Expect

Since your baby is getting big, your uterus is growing too, leaving little room for the rest of your organs!

Because your uterus is pushing up toward your stomach and lungs, you might deal with heartburn and notice yourself a bit short of breath.

On the other end of things, your uterus is pushing down on your bladder, which probably means you have to go to the bathroom frequently and might even leak a little bit.

What To Do

First of all, take lots of deep breaths (literally and figuratively!). If you’re dealing with heartburn, talk to your doctor about what you can do to combat it.

Cut down on nighttime bathroom trips by avoiding drinking water before bedtime. While going frequently is common at this stage, let your doctor know if you have symptoms of a urinary tract infection.

Braxton Hicks Contractions

What To Expect

If you feel tightening in your belly or what seems to be small contractions, you might be experiencing Braxton Hicks contractions, which are common in the third trimester.

Contrary to the real-deal contractions before birth, Braxton Hicks are infrequent and inconsistent, meaning that they don’t occur at regular intervals and will come and go unpredictably.

What To Do

To ease the discomfort of Braxton Hicks contractions, try changing positions. Lying down or going for a walk might help. You can also take a warm bath and drink water or tea.


What To Expect

As you get closer to your due date, you may feel the urge to nest — clean house, prepare your home for your little one, and put the finishing touches on your nursery.

While you don’t want to wear yourself out doing those tasks, your nesting instinct can help you finish last-minute projects to get your baby’s nursery ready.

What To Do

Make sure you have the baby essentials on hand. You should also be sure that your nursery is completely set up, just in case your little one comes a bit early.

Create a nursery that will be a safe and comfortable place for your child to play, grow, and sleep! One of the best ways to do that is by setting their crib up for safe sleep.

baby sleeping peacefully on a newton baby crib mattress.

Purchase a firm crib mattress that fits correctly in the crib. For even safer, more comfortable sleep, put your baby down on a breathable mattress, like Newton Baby’s Crib Mattress.

Our washable mattress is 100% breathable, which helps regulate body temperature and means that your little one can breathe straight through the mattress if they roll over during the night.

Swelling And Varicose Veins

What To Expect

If all this pregnancy weight gain wasn’t enough, you might also find yourself especially puffy during these last few weeks of pregnancy.

Your body is retaining fluids, which appear as swelling in your legs, ankles, feet, hands, and face. Speaking of body fluid and swelling, you might also have swollen veins that are blue or purple and bulge a bit.

Similarly, some women develop varicose veins on their body, even down to their — ahem — bottom. Hemorrhoids, which are varicose veins in the rectum and anus, are not unusual during this trimester.

What To Do

woman in third trimester lying in bed

Combat swelling by staying off your feet and putting them up when you can. If you’re pregnant during the summer months, avoid being in the heat for long periods. Wear comfy shoes and compression socks.

If swelling increases suddenly, talk to your doctor, as you might be dealing with a more dangerous condition.

When To Seek Medical Care

As you’ve probably already figured out, the third trimester is not always a walk in the park. But most of the discomfort is just part of the pregnancy package! However, you should be on the lookout for a few warning signs that could indicate something is amiss.

While this is not a complete list of all third-trimester warning signs, call your doctor as soon as possible if you:

  • Have vaginal bleeding
  • Think your water has broken
  • Have symptoms of a urinary tract infection
  • Notice extreme swelling
  • Have bad headaches that won’t go away
  • Experience pain in your back or abdomen
  • Are vomiting and nauseous
  • Run a fever and have chills
  • Notice that your baby’s movements or kick counts have decreased
  • Are dizzy, have blurred vision, or see spots

When it comes down to it, go with your gut, mom! If something doesn’t feel right, trust your instincts and ask your doctor about it.

The Third Trimester Checklist

Pregnant woman in third trimester

In addition to the changes you’ll notice in your body during your third trimester, here’s one more thing you can expect: you’ll become keenly aware that your baby will arrive in just a few weeks!

If you’re feeling the pressure of getting everything done before the big day comes, first of all, take a deep breath. You don’t want to spend all of this trimester stressed and anxious!

That being said, we know you have a lot to do to get everything ready and in order. To help you stay organized and on top of things, we’ve created this third-trimester checklist.

1) Make Time For Your Doctor’s Appointments

At the beginning of your third trimester, you’ll have a doctor’s appointment every other week. Later on, you’ll go once a week!

Work your schedule around all those appointments so you don’t miss any! They’re important.

Speaking of the doctor, you’ll also need to schedule a time to do your Group B Strep test. You’ll have that done between 35 and 37 weeks.

2) Write Thank-You Notes

Put your feet up and write thank-you notes for all the goodies friends and family brought to your baby showers. If you can do this shortly after the shower, even better!

3) Arrange Childcare

Mom hugging first child

If this is your second baby — or third or fourth! — settle on who will take care of your older child(ren) when you go into labor and head to the hospital. Make sure everyone involved understands the plan.

4) Finalize Healthcare Plans

You want to have all your healthcare ducks in a row before you go into labor. If you haven’t decided on a pediatrician for your little one, now’s the time to make that decision.

Be sure you know how to go about adding your baby to your insurance, too, so you can do so shortly after they are born.

5) Finish The Nursery

Put the finishing touches on the nursery so that everything will be ready in case your baby makes an early appearance! Don’t hesitate to ask for a helping hand with last-minute projects or see if a friend wants to come over and provide some company while you organize.

6) Pack Your Hospital Bag

Just like you’ll want to have the nursery done well before your due date, you should also pack your hospital bag in advance.

There may be some items you’ll keep using up until you go into labor. Pack what you can and then make a list of things to throw in your bag before you walk out the door.

To make sure you’ve got everything, take a look at our hospital bag checklist here.

7) Get The House Ready

Clean your house and stock your freezer! But don’t do it all yourself. Enlist the help of a friend or family member to help tidy the house, or hire a professional cleaning service to come in.

Also, future-you will thank you if you cook a few meals to have in the freezer. You may also want to stock the pantry with snacks for you and your partner to munch on during the first few days at home with your little one.

8) Wash Baby Clothes, Swaddles, And Sheets

baby swaddled

Wash all of your sweet baby’s clothes and swaddles so all that’s left to do is await their arrival. Opt for organic cotton swaddles, like Newton Baby’s Organic Swaddle Blankets. They’re 100% breathable, helping to keep your baby at the perfect temperature and avoid overheating.

Plus, a swaddle like this is extremely versatile — it can double as a burp cloth, light blanket, stroller cover, or nursing cover.

And don’t forget to wash your baby’s crib sheets and put them on their bed. For a practical, breathable, and cute option, use Newton Baby’s Waterproof Crib Mattress Pad underneath Breathable, Organic Cotton Sheets.

Our mattress pad provides a layer of breathability on any mattress, and our muslin sheets add a cute touch to your baby’s crib!

Swaddle blankets

9) Install The Car Seat

You aren’t 100% baby-ready until you’ve installed the car seat in your car. You’ll need it to take your little one home from the hospital, and you don’t want your partner scrambling to do it when you go into labor.

After all, a couple of weeks of driving around with the car seat in your car will just get you even more excited about your little one coming!

Prepare To Welcome Baby

No matter what your third trimester holds, the exciting part is that you’re getting closer and closer to finally snuggling your little one!

Take advantage of these last few weeks before your baby’s arrival to prepare your heart and home for a warm welcome.

Outfit your nursery with Newton Baby products, spend quality time with your partner, and take good care of your own body. Before you know it, you’ll see signs of real labor and your baby will be on their way!

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