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21 weeks pregnant


Foetus at 21 weeks pregnantYour baby at 21 weeks

Your baby is the size of a large banana, but the resemblance ends there.

  • She can taste what you eat through changes in the amniotic fluid - she swallows this on a regular basis - so if you eat a bar of chocolate now she will taste it later. There is some research that suggests what you eat now will influence her food preferences after birth. But you should be guided by what you want to eat - don't feel you have to educate your baby's palate with a selection of foods from around the world.
  • She starts to absorb small amounts of sugar from the amniotic fluid that she is gulping down. But this is just her digestive system practising; she relies on the nutrients from the blood in the placenta.
  • This week your baby starts making red blood cells in her bone marrow (taking over from her liver). How grown-up is that?
  • At 21 weeks your baby's memory is also beginning to develop. She won't remember being in your uterus, but she will find music familiar if she's already heard it in the uterus and she will be comforted by your voice once she is born.  

Your body at 21 weeks pregnant

  • Pregnancy bloom Some women bloom. They really do. They go from feeling like they're dying, spotty, emotionally exhausted wrecks, to being shiny, energetic, bouncy pregnant women. This may never happen to you. The increase in your blood flow should make your face rosy and pregnancy hormones will now plump up your skin so you look five years younger. Your hair will be fuller and shiny and you will ooze health and wholesomeness. Your nails and hair both grow faster in pregnancy. You will feel vigorous and alive (but don't count on it lasting past 9pm).
  • Goodbye thighs At some stage you will say goodbye to your thighs as your growing uterus hides them from view. It will become challenging to wipe your bottom and cut your toe nails. Your feet will spread out because the hormone relaxin does what it says on the tin and lets your ligaments stretch, including those binding together the bones in your feet. So your feet get wider. Do not try to stuff them into your usual shoes because you'll make your feet sore.
  • Anxiety You may wonder if you have the 'right feelings' at this stage in your pregnancy. Do you want this baby enough? Are you relieved that your last scan was fine or has it made it so real that you feel anxious? Mumsnet has lots of posts from women who feel just like you, so head to the Pregnancy Talk board or your MN antenatal club and seek reassurance. It's normal to feel unsure, anxious and unready as well as excited. If you feel sad for prolonged periods of time, or hopeless about the future, then you should tell your antenatal team. Pregnant women are not immune from depression.
  • Itchiness Pregnancy hormones, especially oestrogens, can make you feel itchy. Your palms and soles of your feet may be red and itchy but so can your tummy. All this is normal and due to the increased blood flow. But if you feel itchy all over your body it can be due to an unusual condition called cholestasis of pregnancy, which is a problem with high bile salts being deposited in your skin. This can harm your baby so you need to tell your antenatal team. 



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