Baby development week by week

Week 3

by Stephanie Spencer |
Updated on

Those first few weeks with your newborn baby can be both overwhelming and exhausting and you'll notice your baby reaching all sorts of week-by-week baby development milestones. It can be fun to learn about what you can expect your baby to be doing at each new week of their life.

As a parent, it's normal to have a lot of questions. How should your baby be developing both cognitively and physically each week? What are the common problems to look out for? Your baby will have a newborn health check in the hospital and during the first week since birth. This will include the heel prick test which the NHS says 'involves taking a blood sample to find out if your baby has 1 of 9 rare but serious health conditions.'

To help ease you into your new journey, we’ve broken down what to expect for baby development week by week, from the milestones they will hit, to how much they should be eating and sleeping so you can feel informed and reassured.

Newborn milestones

Week 1

baby development week one1

In week 1 of their development, your tiny newborn might be a little wrinkled and squashed, but they'll be learning how to live in the world. They'll also be sleeping for up to 17 hours a day so get as much rest and recovery time as you can while they're sleeping. One of the most important senses for your newborn is touch, and they will love being held by you, with skin-to-skin contact especially important for both mum and baby.

Week 2

Week 2

Your baby may still be losing weight in week 2 of life as they're not used to feeding yet, however, this will soon stop. The biggest change you might see this week is that their eyes are beginning to focus on things including getting to know your face better. You might also want to take a look at their nails this week - they'll probably need a trim!

Week 3

Week 3

Your baby's nervous system and muscle control are yet to mature, so you’ll find their movements to be jerky still in week three of their development. They'll begin to find the smell of your skin a real comfort to them this week, so keep them close. As for their skin, they should be peeling less this week.

Week 4

Week 4

As your baby reaches one month old, their hearing will be fully developed and their vision is improving by week fourof their lives. Your baby might still be a little cross-eyed this week but they'll be finding their vocal cords more so get prepared for plenty of baby talk as baby begins to try talking.

1-month baby milestones

From that first smile to lifting their head, there are some very exciting milestones ahead this month.

Week 5

Baby development week five

Get ready for baby's first big growth spurt this week! During week 5 of their development, babies will normally gain around 200 grams, so expect a hungrier baby and more nappy changes! This week, you'll notice their movements become less jerky too as they gain more control over their body.

Week 6

Week 6
Father holding his newborn baby girl

It's time for tummy time! In week six of their development, your baby might be able to lift their head as their neck muscles develop. Their memory and hearing are also improving so you want to start reading and singing to your baby.

Week 7

seven week old baby

Your baby has grown almost two inches since birth and is starting to look more like a little person. During week 7 of their development, they're likely to start using their limbs more. As well as this, their eyesight is improving and they're likely to start seeing colours.

Week 8

baby 8 weeks old

Your baby is discovering their arms and legs during week 8 of their development, figuring out how everything works way before reaching baby milestones such as starting to roll over or learning to sit up, which means lots of reaching and kicking.

2-month baby milestones

Week 9

9 week old baby development

As your baby starts to outgrow their Moses basket and smile for the first time, that tiny newborn you brought home nine weeks ago has changed in so many ways. During week nine of their development, you'll notice them looking closely at your mouth as they talk and you may even find they reply with sounds.

Week 10

baby week 10

As your baby starts to fill out more, they'll start to realise they can use their arms and hands, meaning there will be lots of grabbing at things at 10-weeks old. They'll begin to recognise people they know and their social skills will begin to develop so it's a great time to have a family get-together.

Week 11

11 week old baby development

As your baby starts kicking and punching, you'll notice they have more control. Now is a good time to prepare for that first immunisation appointment. They'll also be able to stay awake longer when they reach the week 11 mark and they'll become very inquisitive about the world around them.

Week 12

Week 12 baby development

During week 12 of their development, your baby will get their first set of jabs. You're also in for another growth spurt, which means crankiness, restlessness and a hungrier baby. They're really starting to use their hands more this week so you may want to introduce new textures for them to touch and feel.

3-month baby milestones

Your adorable 3-month-old baby is really developing their own little personality around this time. You'll probably spot their first little laugh around the week-13 mark, as well as improved hand-eye coordination. Baby will soon be on the move too and they'll start to roll over this month. NCT (The National Childbirth Trust) says that from 3 months old, your little one will "begin to turn their head, kick their legs, make eye contact and smile," as they become more playful.

4-month baby milestones

Your baby will be getting plenty of attention when out about as they begin to blow raspberries, laughing a lot and pointing at things. At 4 months old, their eyesight is sharp and by week-20, they can recognise themselves in a mirror and are learning to play. The NHS says that your baby will gradually need less support from 4-months-old as their muscles strengthen.

Stephanie Spencer is the Hub Editor at Mother&Baby and auntie to four aged 8 to 6 months old. With a particular interest in health, she loves discovering products that make parent’s lives easier.

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