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22 weeks pregnant


Foetus at 22 weeks pregnant

Your baby at 22 weeks

She's about 27.5cm long and weighs 430g.

  • At 22 weeks, your baby's legs are now longer than her arms, just as they should be.
  • Her brain is mature enough for her to investigate whatever she touches. Where she once moved away from things, she now reaches for them. Her sense of touch is developing and she will stroke her face and feel bits of her body. She's realising that parts of her body are connected.
  • She's more aware of her environment. She's disturbed by sounds, light and touch and she responds to these by moving.
  • Until the late 19th century, doctors thought babies were born deaf. Now we know that by 22 weeks your baby responds to many different sounds. She can hear a door slam, loud music and constant rhythmic sound of blood going through the uterus. She prefers low intense sounds to begin with. Research shows that playing a newborn baby recorded sounds from the womb will calm her. There's a trend to play babies classical music, read them great works of literature and take them to plays while they're still in the womb. These are worthwhile activities but, however smart your unborn child is, she's unlikely to gain much intellectual advantage from them. She would probably prefer you watched CBeebies.
  • The creases on her palms are developing.
  • She has a cycle of waking and sleeping. She'll nod off a lot but only for short periods of time.
  • Her lungs are growing quickly now - they take the longest to develop. The main tubes in her lungs have buds at the end of them and these alveoli ducts (like air sacs) keep budding. In a month's time, these alveoli will be surrounded by tiny blood vessels so that oxygen can pass from the air sacs into the blood. Before birth her lungs are full of fluid that has lots of chloride, a bit of protein and some mucus. Closer to birth she will start producing surfactant, an amazing chemical that stops the air sacs collapsing when you breathe in and out.  

Your body at 22 weeks pregnant

  • Your brain In a review of the effects of pregnancy on your brain, psychologists from the University of California declared that the changes in hormone levels are not only unique but have a purpose. They get us ready for motherhood by making us better at dealing with stress and putting us in touch with our baby's needs. When your baby stirs at night, you'll sit up immediately while your partner snores on. When your baby moves in your womb it raises your heart rate and increase the rate that messages from nerves are transmitted through your skin. The authors say all these things work to 'optimise' maternal behaviour. However, some of this research has been done on rats. Human mothers are likely to be more complicated.
  • Your emotions You may be feeling anxious about the giving birth bit (or you may have been anxious as soon as your test was positive). Women often worry that it will be so painful they won't cope, or that their waters will break on the bus. Mumsnet, antenatal classes and the NCT can all help relieve your fears, as can friends and family sensible enough not to tell you their favourite labour horror story. You should talk to your antenatal team who will have answers for many (maybe all) of your fears. But what you feel is natural because it's uncertain.



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