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31 weeks pregnant


Baby at 31 weeks pregnantYour baby at 31 weeks

  • Your baby's muscles are coming along nicely and you may see her kicking while you're having a bath.
  • The adrenal glands, which are small bits of tissue sitting on top of the kidneys, are very busy making cortisol. This hormone helps the lungs to make surfactant, essential for breathing as it stops the lungs collapsing after each breath. The adrenal glands produce 10 times the amount of cortisol as an adult gland, showing just how important cortisol is for your baby in helping her lungs develop.
  • Her liver is making bile, which will help her digest fats, and her pancreas is producing insulin to control her blood sugar. Her kidneys are working full speed to filter the fluid she is swallowing and to make urine. But all this is practice because your placenta is doing everything she needs - feeding, breathing and eliminating her waste products.
  • If you are carrying a boy, his testes are moving from the abdominal wall where they starting developing, into this scrotum. If you have a girl, she will be developing her clitoris.
  • The skin on her face is getting smoother and she has more fat all over her body. But she is still a bit scrawny.

Your changing body at 31 weeks pregnant

Varicose veins These are your regular veins that get swollen in pregnancy because your uterus presses on the veins higher up in the pelvis creating dilated veins in your legs. They can be uncomfortable and ache. They can also look unpleasant but after your first baby (at least) they usually go. You can also get them in your vulval area where they feel like a string of grapes. The following can help:

  • Exercise: walk, ride a bike or swim.
  • Raise your legs (higher than your heart, ideally). It may look weird but it stops blood pooling in your leg veins.
  • Don't stand for long periods of time. If you do stand, tighten your calf muscles regularly.

Anxiety There may be some pregnant women who don't feel anxious when they remember their baby has to come out, but most women do get worried. You may not only be anxious about giving birth but also that your baby will be normal.

Talking to other women can be very helpful, but understand some women like to tell horror stories about giving birth, so divide the horror in their stories by at least half. 

The odds of having a healthy baby are overwhelmingly in most women's favour, but we all know that's not guaranteed, which is why we all feel a little anxious. This anxiety for your baby will last for the rest of your life - even when your baby is married with her own baby.

If you're feeling depressed you might find it helps to discuss this with other mums who've been in a similar position - you can post on our Pregnancy forum or our Mental health forum. Whatever you do, don't suffer in silence - if you're finding the going extra tough, talk to your GP or midwife.

Braxton Hicks contractions These are tightenings you feel in your uterus as it limbers up for labour. They're said to be painless contractions but after your first pregnancy can be strong enough to make you stop what you're doing and go "arrghhh".

Braxton Hicks start at the top of your womb and fan out down your uterus making it feel quite hard. They are named after the obstetrician who noticed this phenomenon, John Braxton Hicks, in the 19th century. 

They can last 15 seconds or more and be uncomfortable enough to make you get up, do some breathing exercises or have a warm bath. They are more common in the evening and may go if you change position. 

It is easy to confuse them with real labour pains if this is your first pregnancy. Ask your antenatal team if you are not sure. If you also have lower back pain, this may suggest early labour


Pregnancy Encyclopedia book coverIllustrations taken from The Pregnancy Encyclopedia, £25, published by DK.

Disclaimer: The information in the pregnancy calendar is for general information and is not intended as a substitute for the medical advice of your own doctor or antenatal team. Not all babies develop at the same time and in the same way, so this week-by-week guide may not always match your own experience. If you have any worries, consult your antenatal team or GP.

Last updated: 3 months ago