Baby is a 31-week resident in the womb and weighs about 1.5kg (3.5 lbs). It’s about the size of a coconut, roughly 40 – 42 cm (16 inches or so) long. 

From this point, you could be as close as six weeks from the big day. But before we get there, your baby still has quite a bit of growing to do, and you’re going to feel that progress rapidly. 

pregnancy week 31 fetus weight and size compared to fruit

Your baby at 31 weeks

In utero, babies at 31 weeks will gain weight more rapidly – up to another 1 – 2 kilograms (3 – 5 lbs). As a result, the baby will seem to get plumper and look less wrinkled during this time. All this requires more periods of sleep, but when the baby’s awake, they’ll be more noticeably active. 

Baby moves around more, sometimes changing position, and even starts actively sucking on their thumb. There will also be more amniotic fluid present. This is because the baby has started peeing! 

Hearing voices

Talking to your baby is always a good idea. Studies show that babies can start to hear and recognize voices from outside at this stage. Psychologists believe that this is a good time for parents and siblings to talk to your belly, suggesting that it can help bond the family. 

Brain development

The accelerated growth of a 31-week old fetus means that the baby is entering REM sleep more regularly. But it is also able to start regulating its own body processes like temperature. It is able to use its senses, and with the exception of smell, is able to perceive the world around them.

Your body: What to expect at 31 weeks

You’re pregnant at 31 weeks, and your body knows it’s not long to go now. But over the last 7 months, the adjustments and transformations have been noticeable. Here’s what you can expect at this time.  

pregnant belly 31 weeks
Image by PublicDomainPictures from Pixabay
  • Braxton Hicks contractions. Your womb “tightens” from time to time with these perfectly normal and painless contractions. They are nothing to worry about unless they become painful and regular. In that case, talk to your doula, midwife, or doctor. 
  • Carpal Tunnel Syndrome. It’s not just a symptom of too much office work. During pregnancy, your hands and fingers may become numb or tingly more easily. Try shaking them out often.
  • Cramps and heartburn. A very common side-effect of pregnancy is the occasional heartburn and cramping. 
  • Feeling off-balance and clumsy. Your body is carrying a lot of extra weight and may undercompensate for balance and dexterity. All you can do is take a little extra care and try to avoid potentially unsafe situations. Including unassisted stair climbing, ladders, and carrying heavy items. 
  • Don’t worry about tiredness. Your body is working overtime. So if you’re feeling fatigued, go with it. Naps and breaks are your privileges at this time. Take advantage when you can. 
  • You might develop a “pregnancy brain”. It’s often a topic of fun and games, but forgetfulness or odd-logic decisions are a real thing during pregnancy. In part, it’s the changing balance of hormones that drive this. 

But it may be exacerbated by sleep deprivation (which might get worse as your pregnancy comes along and well beyond). But it’s temporary, and will be good for a few stories at dinner time. 

Taking care of yourself during week 31 of pregnancy 

In all of the excitement of pregnancy, it’s easy to forget that taking care of yourself is as important as taking care of the baby. In fact, one helps considerably with the other. There are a few things you can do:

exercise during pregnancy
Image by StockSnap from Pixabay
  • Try light pilates. A strong body will make for a better birth experience all around. Certain forms of pilates or yoga do show immense benefits during pregnancy, and even at 31 weeks, those able to exercise lightly definitely should. Aside from the physical leg-up, so to speak, you’ll also feel better mentally and emotionally. 
  • Continue with Kegel exercises. Your doctor has probably told you by now to keep up your Kegel exercises. Remember to do them properly, and be especially aware of your back. Doing these incorrectly can lead to additional back pain. 
  • Sleep on your side. By now you’ve probably realised that sleeping on your side is much better than sleeping on your back – in fact, it’s medically advised. Studies show that sleeping on your back has an impact on the oxygen supply to your baby. Just be sure to pack a few pillows in strategic places to assist. 
  • Up your antenatal care. Your medical professional will be keeping an eye on the size and position of the baby at this point. Don’t worry, there isn’t necessarily a problem if the baby isn’t in birth position yet, but they’ll be able to monitor this easily from this point. Your urine will also be tested for protein and your blood pressure will be monitored for safety. 
  • Moisturise. Areas of your body will be expanding. And so will your skin. Welcome to stretch marks! Don’t worry, they’re generally temporary. Your skin may also dry out or become itchy. So take care of it by moisturising generously. 
  • Contemplate some decisions. If you haven’t considered them yet, some questions would be worth addressing from this point. For example, will you breastfeed or go the formula route? Your decision may impact whether you take lactation classes, in this case.  

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