Medically reviewed by Lesley Bland BA (Hons), BSc (Hons) Midwifery Studies
You’ve been on this new journey for over two months already, and now your baby's 9 weeks old you’re probably starting to notice all sorts of milestones in your baby’s development. It's an exciting time, as your baby starts to become even more engaged with the world and you might be starting to think about settling into a sleep routine of sorts. From sleep patterns to baby growth spurts, we’re here to answer all your questions about your 9 week old baby's development with the help of expert guidance from Maternity Nurse and Baby Sleep Expert, Jo Tatum and Registered Midwife, Lesley Bland.
9-week-old baby physical development
• Growth: Your little one will have grown about two inches since being born and probably gained a few pounds and it's likely they'll grow another inch this month. You should have had a 6-8 week check-up where the doctor will have checked your baby's eyes, heart, hips and – for boys – testicles. They'll also measure your baby's weight, length and head circumference so you should have a good idea of where they are on their centile chart.
• Muscle control:
As they’re gaining weight, they’ll start to fill out a bit, giving them those adorable chubby baby thighs and arms. Those little legs and arms will likely be constantly moving nowadays, always kicking and shaking with excitement. Your baby, week by week, will show more coordination and control over their seemingly jagged movements and the kicks and punches they learnt at the 8 week baby stage are becoming stronger.
Babies at 9 weeks may now be able to raise their shoulders during tummy time, but don’t worry if their neck muscles aren’t strong enough yet, every baby develops at a different pace and before you know it, they'll be using their arms to support themselves.
• Grabbing: With your baby noticing more things on people’s faces and sounds around the room, their new interest may lead to over excitement and a lot of grabbing. As they develop their arm and hand muscles, expect to be grasped and grabbed all the time. Now might be the time to avoid those dangly earrings.
• Making new friends: With your baby more alert and sociable during the day, it’s a good week to organise play dates and get out of the house more. As you start to settle into life with a baby, it's good for both of you to visit baby sensory groups to meet other parents and babies. You’ll both be better off for a bit of outside interaction. Meeting new friends with babies can be a chance to compare notes and share stories, and there are various social apps to help you find parent friends.
9-week-old baby cognitive development milestones
• Baby babble: As well as this physical development, they will be making all sorts of noise! It’s a great chance for them to develop their ability to identify sounds, their coordination and muscle control. They also want to hear you speak and hear the different tones and pitches in different voices, so keep chatting to your baby and give them a chance to coo in response. Researchers have found that this baby babble lays the foundations for their future speech so it might seem a long way off but interacting with them will help their speech development further down the line.
• Listening skills: Your baby’s understanding of sound will greatly improve this week too, so keep chatting and singing to them. If you're wondering when your baby will start smiling, you'll be pleased to know that they will very soon! So keep chatting and you might get to see that gummy little smile!
You may notice your baby has different reactions to noise now too, so it’s a good idea to play a gentle lullaby for when you want to introduce nap time.
While your baby’s hearing has been fully developed for weeks now, they will start to be more interested in the sounds they hear, which is why their reactions differ so much. Nine weeks is a good time to give them their first rattle as you’ll notice them excitedly trying to work out where the sound comes from, shaking it non-stop!
• Sight: Another sense your baby is developing is sight. They should show much more interest in different faces this week and into week 10 of baby's development, as their 3D vision develops. You’ll see them staring intently trying to figure you and other family members out. A 9 week old baby can see objects about eight inches in front of them and they may start turning to identify where a sound or face is in the room. It’s a great time to bond with your baby and watch them smile when they see your face.
9-week-old baby jabs
You should have had your first immunisation appointment at 8 weeks, but if you’re only just fitting it in or they had to be postponed, check our baby vaccine calendar for upcoming jabs to be aware of. Following the NHS vaccination schedule, you can expect to be offered vaccinations at 8 weeks, 12 weeks, 16 weeks and 12 months old, and before your child starts school.
• 6-in-1 Vaccination: During their 8 week vaccination appointment, they’ll receive their first dose of the 6-in-1 injection against diphtheria, tetanus, whooping cough, polio, hepatitis B and Hib (haemophilus influenza type B).
• Rotavirus: They'll also get their first Rotavirus vaccine (which is a common cause of diarrhoea and sickness) and this is given orally (a liquid dropped into their mouth).
•MenB vaccine: They'll also receive their first MenB injection which protects against bacterial infections caused by meningococcal group B bacteria (MenB), including meningitis, septicaemia and sepsis.
The injections for the 6-in-1 vaccination and MenB are given in their upper thigh, one injection for each leg. It might sound traumatic, but should only take a few seconds.
You may need to postpone the immunisations further if your baby has a fever, diarrhoea or are very unwell, but if they just have a cough or cold they should go ahead just fine. Watch out for the fever they may get from the MenB vaccine, your nurse may advise you to give your baby infant paracetamol if a fever does develop.
9-week-old baby sleep
Your baby should be starting to sleep in solid blocks at night, usually about five to six hours. Of course, it’s different for each baby and other hours are still completely normal so don't worry if your baby is still waking up more regularly, or even sleeping for longer. While there's no recognised sleep regression at 9 weeks, that's not to say you'll be getting a full night's sleep.
However, as their night time sleeps get longer, their daytime naps might be getting shorter. They’ll be sleeping on average between 11 and 15 hours per day, with naps becoming less frequent but longer, giving you more time in the day to get things done or relax.
To relax them before bed, try feeding at about 10pm or just before you go to sleep yourself, as it will induce a sleepiness that should tide them over until they wake in the night for a feed.
You could try establishing a little bedtime routine for your baby now too. This can include having a warm bath, reading them a story and feeding them too. This can help them get used to associating night with going to sleep.
Swaddling should still be coming in handy, but your baby’s growth spurt may be taking a toll on the wrap now. You can also use a baby sleeping bag. Also, make sure your baby is not overheating if it’s summer – it’s a good idea to keep a close eye on the temperature in your baby’s room.
9-week-old Feeding
After gaining almost three pounds since birth, your 9-week old baby is sure to be feeding more than when they were a newborn. As they continue to experience different growth spurts, they’ll be feeding more, usually about six to eight feeds over 24 hours is normal at this age but just keep following their lead for when they are hungry.
How many ml should a 9 week old baby drink?
Parents who chose to feed their baby using a bottle will be able to measure how much baby takes at each feed, be that formula or expressed breast milk. However, those parents who choose to exclusively breastfeed often worry about how much their baby is taking and feel pressured by talking about mls or ounces per feed. To reassure any parent who is exclusively breastfeeding, Lesley Bland from My Expert Midwife advises that "if your baby is gaining weight, pooing and weeing as expected and behaving normally for them, then your baby is likely to be getting exactly what they need. It is important to be responsive to your baby’s feeding cues and follow their lead, in other words, let baby tell you when they want a feed and for how long."
If you choose to introduce a bottle for your baby, whether that is exclusively bottle-feeding or combination feeding, you will be more aware of how much your baby is taking but the same rules apply with baby-led feeding. Let your baby guide you when they are ready for a feed and how much they want to take rather than following a set plan of feeding. You may find that, just as our appetite alters throughout the day, so does your baby’s; they may want more at some feeds and less at others.
A useful rule of thumb is to offer baby 150-200ml (5 – 7 ounces) per kilo of their weight, but again, let them guide you with how much they want to take. However, if your baby doesn't want to feed, and is not gaining weight, and not pooing or weeing, your healthcare team will advise a feeding plan that will be more prescriptive about how much baby should take at each feed.
Paced Feeding
Regardless of whichever milk you choose to give your baby via a bottle, Lesley recommends paced bottle feeding. "This method gives your baby more control of the feeding process while at the same time creating the position and closeness of breastfeeding. By slowing down the flow of milk into your baby’s mouth it allows your baby to take regular breaks and, therefore, control the pace of feeding." This advice is echoed by the NHS.
9-week-old baby - nappies
As they’ve gained weight and height, they’ve been feeding much more and therefore pooing more. However, many babies only poo once per day and some will fill their nappy a lot more frequently – anywhere between one and ten nappies a day is fine. If your baby is going less than three times per week, or seem uncomfortable or in pain when they go, they may be constipated and need to see a doctor. Your baby's poop colour can tell you a lot about the health of their digestive system too.
What problems should parents of a 9-week-old baby be aware of?
Daytime sleep
Daytime sleep is important for development, but some babies start to struggle to nap at 9 weeks. Baby sleep expert Jo Tantum advises: 'Watch for their tired signs – rubbing eyes and ears, staring into space, getting grumpy, yawning, then take them into their room. Total blackout blinds, sleeping bag and cuddles, try wave sounds to help calm them, too. Try giving them a comforter to hold – I suggest a muslin square knotted in the middle as this helps as their motor reflexes are wanting to grab things so this can really help comfort them.'
Colic
If your 9 week old baby is crying more than usual it could be that they're suffering from colic (defined as uncontrollable crying for more than three hours a day, three times a week for at least three weeks). They’ll usually settle in a few weeks, however Lesley Bland and the midwives at My Expert Midwife suggest trying the following to try to help them calm down:
• A nice warm (not hot) bath may help to relax and calm your fractious baby – some parents find that swaddling their baby for a bath can also help
• Skin-to-skin has been known to have calming benefits for babies and parents alike.
• White noise can be used to soothe upset babies – you can turn on an appliance that naturally produces white noise, such as a washing machine or vacuum cleaner, or even a White Noise app on your phone or tablet
• Hold your baby face down, across your arm or lap, or upright against your shoulder, and gently massage their back using a baby-specific massage product. This simple massage can help bring gassy bubbles together, making them easier to expel
• Loosely swaddling in a muslin or blanket can make them feel safe and calmer
• Wearing your baby in a sling around the house & for outings. Their closeness to you, the rocking motion, and the pressure of their tummy against you will help soothe them
• Go for a walk with your baby placed in a pram, wrap or sling, or go for a drive with the baby in a secure car seat
• Gently rock your baby in your arms or a rocker chair
• Discuss with your healthcare providers about using an over-the-counter colic remedy
• Keep a food diary if you are breastfeeding your baby. They may be sensitive to something that has been passed to them via your breast milk. Caffeine, alcohol, and dairy are often recognised as potential triggers, but other foods can also trigger sensitivities.
If you suspect your baby is crying from pain or because they are unwell, always seek advice from a healthcare professional immediately. You can contact your GP, Midwife, Health Visitor or NHS 111. Or take them to A&E or ring 999 if there is an emergency.
Crying
Even if you haven’t been dealing with colic you might be starting to wonder exactly why your baby is crying. All of this growing takes a toll on your baby, so they may be crying because they are frustrated, plus the usual hunger and sleepy cries that you’re probably used to by now.
Postnatal Depression
Postnatal Depression can occur at any time in the first year of your baby’s life. With one in ten women suffering with postnatal depression, you’re definitely not alone. It's important to understand the signs and seek help as soon as you can.
About the experts
Lesley Bland
Lesley Bland is a Registered Midwife and Consultant Midwife for My Expert Midwife. She began her Midwifery career working in large teaching hospitals rotating through all clinical areas with particular emphasis on antenatal and intrapartum care. Lesley qualified as a mentor of students and developed a passion for education specialising as a Clinical Educator teaching the maternity multidisciplinary team.
Jo Tantum
With over 27 years experience working with babies and parents worldwide, it's no wonder Jo Tantum is the UK's leading Baby Sleep Expert, teaching babies how to love sleeping with calm, gentle guidance, encouraging confident parenting.
Rebecca Lancaster is a Digital Writer for Mother&Baby, drawing on ten years of parenting her two children to help others navigating their own parenting journey. As a freelance writer, she spent ten years working with leading lifestyle brands, from travel companies to food and drink start-ups, and writing everything from hotel reviews to guides to the best British cheeses. She’s particularly interested in travel and introducing her children to the excitement of visiting new places, trying different foods (less successfully) and experiencing different cultures.