Your pregnancy: A week by week fetal development guide

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  • Having a baby is an amazing thing, and following your little one through their fetal development stages while you’re pregnant is fascinating.

    There’s certainly lots to learn, so if you’re interested in how your mini-me is growing then we’ve put together a guide to show you exactly how your baby is changing during their nine months inside your tummy.

    From the first few weeks of fetal development, when your baby is technically a ball of cells, through their transformation to an embryo and right up until your little one’s birth – this guide sees you through every week in confidence.

    If you’re having twins, we’ve included information on how they will develop, too, and the changes you can make to help give your baby (or babies!) the best possible support while they grow.

    You’ll learn all about how big your baby is growing during its fetal development stage, how much they weigh and all the things they’re learning, too. There are some surprises along the way (like how early they get finger nails!) and some useful information on scans, check ups and appointments.

    Click on the image below, depending on what pregnancy week you’re currently in, to learn more…

    Week by week fetal development guide

    Week 1

    Week 2

    Week 3

    Week 4

    Week 5

    Week 6

    Week 7

    Week 8

    Week 9

    Week 10

    Week 11

    Week 12

    Week 13

    Week 14

    Week 15

    Week 16

    Week 17

    Week 18

    Week 19

    Week 20

    Week 21

    Week 22

    Week 23

    Week 24

    Week 25

    Week 26

    Week 27

    Week 28

    Week 29

    Week 30

    Week 31

    Week 32

    Week 33

    Week 34

    Week 35

    Week 36

    Week 37

    Week 38

    Week 39

    Week 40

    How far along are you? We love hearing all your pregnancy stories, so if you’re expecting then leave us a comment in the box below telling us how you’re feeling, what stage you’re at and any tips you’ve got for fellow mums-to-be!

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