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34 weeks pregnant


Baby at 34 weeks pregnantYour baby at 34 weeks

  • Your baby's lungs are still developing. The number of tiny air sacs (essential for oxygen to get into her body via the lungs) are increasing all the time. Their walls are getting thinner so the oxygen can get through faster. There is less of a gap between the walls of the air sacs and the tiny blood vessels that carry the oxygen round the body. Before birth, your baby's lungs are full of fluid because she swallows amniotic fluid. This fluid is full of protein, chloride and surfactant that keep the air sacs open.
  • As your baby practises breathing in your womb she breathes in amniotic fluid. This helps the lungs develop and gives the muscles in her chest, which will do all the breathing when she's born, something to do. When your baby is born, her breathing will squeeze this fluid out of her lungs and through her mouth and also into the blood vessels of the lungs where it will be absorbed.
  • Every day of development makes a difference. If she is born this week she may need some help breathing, but in two weeks time she will be able to breathe on her own.
  • As she makes more surfactant - the substance that allows the air sacs to open and close - some of it gets into the amniotic fluid. This seems to set up a chain of reactions that tells the uterus that your baby's lungs are ready to be born because she'll be able to breathe.
  • Her brain is continuing to develop and her head is growing. But if you're worried about her big head getting down the birth canal you should know that the bones of her skull don't fuse together until after birth. They are flexible and overlap as you push her out.
  • She is now 15% fat and more cuddly.
  • Her gums look ridged but her teeth are up to six months away although, rarely, babies are born with a tooth or two.

Your body at 34 weeks pregnant

  • Eating You may feel you could eat a horse but when you sit down to a meal you can barely manage a hoof. Having a large baby inside a large womb pressing on your stomach means you'll do better eating little and often. You may find that you feel sick or even are sick because of the mechanical discomfort of a baby on your stomach and progesterone slowing down the food leaving the stomach.
  • Your size You may feel huge and unwieldy. If you start leaking colostrum from your breasts you may feel enough is enough and want your old body back - the one that didn't leak fluid. Swimming is great for making you feel weightless again, although you will notice the difference in heaviness after you have your baby and go swimming again.
  • Planning the birth You may want to plan what sort of birth you have. Talk to your birth partner and antenatal team in that order, so there are no surprises. Broad topic areas include: who will be with you, where you want to have the baby (this may be decided already), do you want trainee midwives and medical students, will you have your membranes ruptured, what pain relief do you want, how mobile do you want to be, what position do you want to push in and who do you want to cut the umbilical cord? There are many more questions. A quick glance at our Pregnancy Talk forum will confirm this - but you'll also get loads of answers.
Regular tilt exercises can help back pain

• Lie on your back with your knees bent
• Pull in your lower abdominal muscles, squeeze your buttocks and press the curve of your spine into the floor.
• Hold this for 10 seconds and repeat five times.
• Try to build up to 10 repeats.
  • Sciatica and back pain Sciatica is quite common in pregnancy and it hurts. It is due to a large nerve that runs down the back of your leg being compressed. You'll feel sharp, constant pain in your lower back that shoots down the backs of one or both legs as well as pins and needles. The pain can make you feel sick and keep you awake at night. If your pain or weakness in a leg becomes bad, you need to see your doctor. Otherwise, some women find support belts help - they go under your bump and fasten round your pelvis. Follow instructions to make sure you wear it properly. 
  • Coccygeal pain Some women feel pain in their coccyx – the tailbone at the bottom of the spine. It can be tender to sit down on your bottom. You'll feel pain at the base of your spine or in your buttocks. Try to take the pressure off this area by sitting up straight and not slumping. This area takes a lot of pressure, so is vulnerable to getting sore.



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