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27 weeks pregnant

Your baby at 27 weeks

Pregnancy week 27

At about 38cm long, she is an amazing three to four times as long as she was at 12 weeks.

It is hard to hear things through a pea soup of amniotic fluid, but your baby at 27 weeks is trying to make out what's going on outside. All of her organs are developing.

Her lungs, heart and liver are getting more mature and each day makes her more likely to cope if she was born now (she would still need a lot of help).

  • Her long bones are starting to make red blood cells.
  • She is getting chubbier but it's a slow process. Less than 5% of her body now will be made up of fat. But she will look more babyish as the rest of her body catches up with her head (but not fully, she'll still be a bit top heavy at birth).
  • She is practising her proper swallowing reflexes, gulping when fluid gets to the back of her throat rather than randomly swallowing.
  • The hair on her scalp is getting thicker and longer.

Your body at 27 weeks pregnant

Carpel tunnel syndrome Are you getting tingling in your hands? If it only affects the thumb, first and second and half your fourth finger then you have carpel tunnel syndrome.

It happens because the nerve that supplies this part of your hand is squashed in the tunnel of bones in your wrist. It's squashed by the extra fluid you retain in pregnancy. It will go after birth but it's annoying and unpleasant.

Make sure your elbows are not higher than your hands when working at a desk. You can wear wrist splints to take pressure off the nerve.

Snoring The combination of extra weight and swollen mucous membranes in your nose disturbing the air flow makes snoring almost inevitable. Hopefully, you won't wake yourself up.

Pre-eclampsia Most swelling in pregnancy is harmless but you need to know about pre-eclampsia because it is dangerous if you don't get treatment. With treatment you and your baby should be fine, so this information isn't meant to scare you but to remind you to watch out for the signs of pre-eclampsia.

Pre-eclampsia is rare before 20 weeks and most women who get it have it from this week (week 27) onwards. An antenatal appointment might pick it up by finding you have high blood pressure and protein in your urine.

You may get swollen ankles, feet, fingers and your face may get puffy. This is called oedema and it's common in pregnancy. It's your face and hands getting swollen quite quickly that can be warning signs of pre-eclampsia. Also, if you can press your thumb into your oedema and it stays indented (called pitting oedema) it may indicate more established swelling that needs looking at. Later you may get bad headaches and blurred vision.

Some women feel terrible and have a sense that they are seriously unwell.

If you think you may have pre-eclampsia, speak to a doctor or midwife straight away. It is so much better to get it checked as it can lead to convulsions. If pre-eclampsia has been grumbling on for a while, your baby may grow more slowly because the placenta doesn't work as well if you have pre-eclampsia. 



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: 4 months ago