Your baby’s development

At 31 weeks pregnant your baby is about 41cm long and starting to pile on weight – now weighing about 3lb 3oz. The parts of their brain responsible for memory are starting to develop. But how do we know? One study found that babies who were played the theme tune to a popular soap while in the womb responded to it after birth, unlike those babies who hadn’t heard it before birth. You’ll never watch EastEnders in the same way again!

31 weeks fetus
Broccoli pictogram

Baby on board! Explore your pregnancy journey

Discover something new about your baby's development every week, with exciting emails tailored to every stage of your pregnancy.

You & your body

You’re probably feeling quite breathless at the moment and this sensation will probably stay with you during your pregnancy, until your baby drops down into your pelvis. This usually happens at around 36 weeks for first-time mums, but for subsequent babies it may not happen until the beginning of labour.

Your uterus is so large that it’s pressing up against your diaphragm (which is the muscle that usually controls your breathing) so there’s not much room for lots of air. You can help yourself by relaxing which means rest, rest and more rest!

Shortness of breath can also be a sign of anaemia so it’s best to check with your midwife to make sure you’re fine. Read more about common health worries and get tips on how to help!

Did you know?

Until now your baby has been covered in tiny hairs called lanugo, which help to keep them warm before they’ve put down enough fat. It’s around this week that it begins to disappear.

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