Im 31 Weeks Pregnant How Big Is My Baby

Now that you're 31 weeks pregnant, your baby's brain is getting more sophisticated and he's more active than ever in there — pedaling his feet, sucking his thumb and practicing other important skills for the real world.

Your Baby at Week 31

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This week your baby finally comes to his senses. That's right, all five senses are now operational. Even though your little one is just over three pounds and only 16 to 18 inches long, he's now prepared to fully experience the world that waits just outside his quiet cocoon.

His eyes can now perceive light with fully functioning irises that dilate and contract. And those ears, though tiny, not only can hear, they can distinguish sounds: Studies show that fetal heart rates actually speed up and slow down in response to different music. And while there's no air underwater for your little minnow to breathe in, his nose is ready for smelling.

And sniff he does, getting a sense of your scent from the amniotic fluid that passes through his nasal passages. Once he emerges, those first real inhalations of air will take in your special mommy aroma, further imprinting it as the one closest to his heart…and helping him feel as at home in your arms as he did in your womb.

He's also exploring with his new senses, playing with his nose, toes, umbilical cord, and your uterine walls to hone his sense of touch. And by opening his little mouth, and tasting and sucking his thumb, he's getting ready for the good stuff that'll be coming down the pike in just a few short weeks.

Now that his brain is processing the barrage of signals coming in from his senses, cranial connections are multiplying at an astonishing rate. Cerebral development is in high gear and will crank along at breakneck speed for the next several weeks, even after your budding genius has made his grand entrance.

At a Glance

Brain connections

Your baby's brain connections are developing at a rapid pace, which is a good thing since he has to make billions of them!

Sleepy baby

Your baby is a drowsy one, putting in longer stretches of snooze time, specifically REM sleep. Want to wake him up? Eat or drink something sugary.

Such a smarty

Your brainy baby can already process information and pick up signals from all five senses.

31 weeks pregnant is how many months?

If you're 31 weeks pregnant, you're in month 7 of your pregnancy. Only 2 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 31 weeks?

Weighing in at 3-plus pounds and measuring about 16 inches long, your baby is quickly approaching his birth length — though he's got to pack on another 3 to 5 pounds before delivery day.

Baby is sleeping more

He's putting in longer stretches of sleep, which is why you're probably noticing more defined patterns of wakefulness, movement and rest.

Baby's developing five senses

Your baby's brain is working overtime these days, developing faster than ever. Connections between individual nerve cells — he's got to make billions of them! — are being made at a super fast rate. He's now processing information, tracking light and perceiving signals from all five senses.

Sure, your baby may not be able to smell too much right now, though he likely can smell and taste different foods you eat through the amniotic fluid as well as catch a whiff of some beauty products you use (which also wind up in the amniotic fluid).

Lucky for you and your baby, yours will be one of the very first scents he breathes in, a scent that will quickly become his very favorite.

Pedaling his feet and sucking his thumb

So what's your little dove doing all day while you're busy feathering your nest for his arrival? Making faces, hiccupping, swallowing, breathing, pedaling with little hands and feet along your uterine wall, and even sucking his thumb. In fact, some babies suck their thumbs so vigorously while in the womb that they're born with a little blister on their thumbs!

Your Body at Week 31

Shortness of breath

So your stomach feels like it's in your chest and your lungs feel like... Hmmm... They don't even feel like they're there anymore, do they?

Movin' on up at 31 weeks pregnant, your uterus can now be felt about 4 inches above your belly button. This means that your uterus is pushing all the internal organs that used to be there somewhere else, crowding your diaphragm and lungs and making it more difficult for them to expand fully.

The result: Your body is spare on air and will be until your baby drops near the end of pregnancy in preparation for birth. While this shortness of breath may feel very uncomfortable to you, your baby is as happy as a clam because he's getting his oxygen from the placenta.

That out-of-breath feeling may get better toward the end of your pregnancy, when your baby drops down into your pelvis in preparation for delivery. Until then, be sure to stand as straight as you can given the weight you're carrying around, eat smaller, evenly-spaced meals and sleep propped up on your left side so that your lungs have more space to... well, breathe.

How a baby responds to sex

Sex and orgasm can have an interesting effect on babies in the womb, as you may have noticed. Some are very quiet after their parents have sex — rocked to sleep by the rhythmic movement, perhaps — while others become frisky themselves (hey, where's the party?).

Both responses are completely normal and in no way indicate that your baby is aware of the goings-on...just that he's having fun going along for the ride.

So keep on enjoying your sex life as much as you like and for as long as you can — which, with your practitioner's approval and a few advanced Twister-type moves, can be right up until delivery day. Pretty soon, jumping into bed together with a baby in the house won't be quite so easy or convenient.

Pregnancy Symptoms Week 31

More frequent urination

Your uterus puts more pressure on your bladder in the third trimester, giving it less room to store urine. Cut down on the bathroom trips by double voiding: Pee, then when you're done, pee again. That'll make sure you've emptied your bladder completely. Read More

Backaches

That burgeoning belly can also do a number on your back as it curves to accommodate the load. If you haven't already, now is the time to incorporate some prenatal yoga into your exercise routine. The stretches will relax your back — and your mind! Read More

Clumsiness

Your shifting posture, your increasing girth and your lack of concentration may make you clumsier these days. Take it easy when you're climbing into the shower or tub and roll up any area rugs that could trip you up at home. Read More

Pregnancy brain

Welcome to mommy-to-be brain — a condition that's a result of shrinking brain cell volume in the third trimester. Don't worry — your brain cells go back to normal a few months after delivery. Don't stress out about your foggy memory, since stress just makes it worse. Write things down or program them into your smartphone and delegate responsibility if possible. Read More

Sleep problems

This is another common third trimester woe, caused by a constellation of other conditions, such as leg cramps, heartburn, frequent urination and plain old anxiety, with a dash of pregnancy hormones. If tension keeps you tossing and turning all night, talk it out with friends or your partner during the day. Read More

Occasional headaches

If tension is twisting your head up in knots, try spending a few minutes in a dark, quiet room. If you're at work, close your eyes and put your feet up for 15 minutes. It's also generally safe to take acetaminophen occasionally when nothing else seems to relieve the pain. Read More

Tips for You This Week

Skip bumpers

Buying or registering for a crib set? Skip the bumpers. Cute as they may look, they pose a serious sudden infant death syndrome (SIDS) risk. Ditto for pillows, stuffed animals and blankets.

Pack your hospital bag

Delivery day is getting close, so it's time to pack your hospital bag if you haven't already.

Along with necessities, you may want to stash these feel-good items inside: lip balm since your lips may become very dry, even before you start breathing heavily during labor; bands or scrunchies to keep your hair back; a brush for tangles (plus having someone brush your hair may feel relaxing); moisturizer; warm socks and slippers; mints; flip-flops (if your feet swell) and a warm robe.

They just might make your labor, delivery and overall stay more comfortable. Remember, don't bring or wear anything you really love, like your favorite PJs or that fancy negligee, since it may get lost or ruined. And check if you need to pack your hospital bag differently in light of COVID-19.

Monitor facial swelling

It may not be just pregnancy weight. If you notice sudden facial swelling, talk to your doctor.

Along with changes in vision and headaches, swelling can be a sign of preeclampsia, a disorder that generally develops late in pregnancy, after week 20. It's characterized by a sudden onset of high blood pressure, severe swelling of the hands and face, and signs that some organs may not be working normally, including protein in the urine.

Drink plenty of H2O

In case you haven't noticed, the heat's on when you're expecting, especially as you get bigger and bigger. But water keeps the body's cooling system running smoothly, even when your inner thermostat is on high, by dispersing excess heat in the form of sweat.

Plus, an ample flow of fluids keeps pregnancy fatigue in check — one of the first symptoms of dehydration is exhaustion — and headaches at bay.

What else can water do? It babies your skin when you've got that itchy and scratchy feeling. Water combats dry skin by keeping you hydrated from the inside out, leaving you almost as soft as your baby-to-be's bottom. More oily than dry and more pimply than smooth? Raise your water glass to a clearer complexion.

Choose comfortable shoes

The best prescription for swollen feet and ankles isn't the most fashionable one: sensible, comfortable shoes that breathe and aren't too tight.

Don't have any that fit that description? That might be because your feet have spread so much that they've actually grown a half size or so — and pregnant feet tend to do that.

Get yourself to a shoe store — but do it at the end of the day, when your feet are at their puffiest. While you're at it, get a pair of elasticized slippers and wear them whenever you can get away with it. And be sure to have some flip-flops on hand for postpartum swelling of the feet and ankles, which can happen as the pregnancy fluids are leaving your body after you give birth.

You can also try support hose to relieve pregnancy swelling. No they're not sexy, but they can be the difference between a swell day and a not-so-swell one. Put them on first thing in the morning, before your feet have a chance to puff up.

If you can't track down ones made for pregnancy, knee- or thigh-highs should do the trick. But avoid any that have uncomfortable elastic tops.

Prevent varicose veins

We know you're not a fan of them, but varicose veins, or swollen blood vessels, are usually painless and harmless.

The reason they develop or get more pronounced during pregnancy is because you've got more blood pumping through your body, and your growing uterus is pressing against veins in the pelvic region, allowing all that extra blood to pool in your legs. Hormones only add to the problem by causing blood vessels to relax.

What to do? Some good varicose vein remedies: Exercise daily to improve circulation, take frequent breaks from sitting or standing, try not to gain too much weight, elevate your legs as often as possible, and sleep on your left side to relieve pressure on your main blood vessels.

Do simple stretches

Chances are, you're carrying a lot of tension in your neck, especially now that you're in the third trimester and your posture is off-kilter. The result can be, well, a pain in the neck.

One way to loosen your muscles and relax your mind: Do this easy stretch — anytime, anywhere. Start by tilting your head to one side, without raising your shoulders; try to melt them down the back instead. Hold for three seconds and exhale. Repeat on the other side.

Do this several times a day — at your desk, while you're waiting at your practitioner's office or in line at the post office.

From the What to Expect editorial team and Heidi Murkoff, author ofWhat to Expect When You're Expecting. What to Expect follows strict reporting guidelines and uses only credible sources, such as peer-reviewed studies, academic research institutions and highly respected health organizations. Learn how we keep our content accurate and up-to-date by reading our medical review and editorial policy.

• What to Expect When You're Expecting, 5th edition, Heidi Murkoff.
• WhatToExpect.com, Safe Sleep Tips for Babies, February 2020.
• WhatToExpect.com, Hospital Bag Checklist, May 2021.
• WhatToExpect.com, What to Pack in Your Hospital Bag During the COVID-19 Pandemic, January 2021.
• WhatToExpect.com, How Much Water Should You Drink During Pregnancy?, December 2020.
• WhatToExpect.com, The Best Stretches to Do During Pregnancy, October 2020.
• WhatToExpect.com, Varicose Veins During Pregnancy, March 2020.
• WhatToExpect.com, 11 Best Home Remedies for Varicose Veins When You're Pregnant, December 2020.
• WhatToExpect.com, Edema (Swelling of the Ankles and Feet) During Pregnancy, October 2020.
• WhatToExpect.com, Is Postpartum Swelling Normal?, April 2020.
• WhatToExpect.com, Fatigue During Pregnancy, November 2020.
• WhatToExpect.com, Preeclampsia: Symptoms, Risk Factors and Treatment, May 2021.
• American College of Obstetricians and Gynecologists, How Your Fetus Grows During Pregnancy, August 2020.
• American College of Obstetricians and Gynecologists, Preeclampsia and High Blood Pressure During Pregnancy, December 2020.
• Centers for Disease Control and Prevention, Water and Nutrition, January 2021.
• KidsHealth From Nemours, Bringing Your Baby Home, June 2018.
• March of Dimes, Shortness of Breath, August 2009.
• Mayo Clinic, Fetal Development: The 3rd Trimester, June 2020.
• Mayo Clinic, Sex During Pregnancy: What's OK, What's Not, July 2020.
• Mayo Clinic, Varicose Veins, January 2021.
• National Heart, Lung, and Blood Institute, How the Lungs Work, October 2020.
• National Institutes of Health, National Heart, Lung, and Blood Institute, Varicose Veins, 2021.
• National Institutes of Health, National Library of Medicine, Dehydration, October 2020.
• National Institutes of Health, National Library of Medicine, Sex in Pregnancy, April 2011.
• Stanford Children's Health, Aiding Baby's Emotional, Intellectual Development, 2021.
• The Urban Child Institute, Baby's Brain Begins Now: Conception to Age 3, 2019.
• American Journal of Radiology, Change in Brain Size During and After Pregnancy: Study in Healthy Women and Women with Preeclampsia, January 2002.
• JAMA Pediatrics, Denouement and Discussion: Congenital Sucking Blisters, June 2007.
• National Institutes of Health, National Library of Medicine, Pediatrics, Prenatal and Postnatal Flavor Learning by Human Infants, June 2001.
• National Institutes of Health, National Library of Medicine, Symmetrical Erosions in a Neonate: A Case of Neonatal Sucking Blisters, July 1998.

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Im 31 Weeks Pregnant How Big Is My Baby

Source: https://www.whattoexpect.com/pregnancy/week-by-week/week-31.aspx

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