12 Week Old Baby | Your Baby Week By Week

12 Week Old Baby | Your Baby Week By Week

Your 12 Week Old Baby

You have a 12 week old baby! Three months. The fourth trimester. You did it!

Most parents will tell you the first six to twelve weeks are the hardest. Whether this is true or not, surviving them is worth celebrating. Your baby has made amazing progress since leaving the womb, and has grown more quickly than he ever will again. You’ll see a plateau in physical growth for a while, as brain development takes priority in preparation for the next big challenges: mobility.

You’ve also made huge progress in your parenting journey and probably feel more confident understanding your 12 week old baby’s needs. At the same time, you might be wondering about combining parenting with your return to paid work and how on Earth you will have time for all you need to do. It will be helpful to read our article, Going Back To Work After Baby – 5 Tips For A Smooth Transition.

Wonder Week – Leap Three

If your baby was born on her due date, around twelve weeks he will experience the third Wonder Week. This Leap is about the world of smooth transitions. Once again, you can expect the three Cs – clinginess, crankiness and crying again during this time.

You’re likely to most notice this leap in his physical movements – his arms and legs will seem less jerky, their movements more controlled. His thinking will be a little more organised by the end of this leap too – he’ll know the things you do just before feeding him and might get excited or frustrated when he sees you prepare.

Feeding Your 12 Week Old Baby

Your 12 week old baby is very efficient at feeding now and will sometimes finish a feed in only 5-10 minutes. You might start to notice some early distractibility during feeds and can expect this to increase, peaking around 4 months. Night feeds continue to be important, though some babies have longer stretches of sleep between 3-4 months, this is usually temporary and increased waking can be expected again during significant developmental leaps still to come.

It continues to be important to correctly clean your feeding equipment if you bottle feed, whether you use your own expressed breast milk, donor milk or infant formula. Breastmilk expressing and feeding equipment needs to be thoroughly rinsed in cold water after each use and washed in hot, soapy water once every 24 hours. If you are expressing less frequently, then rinse and wash after each use.

If you are feeding your 12 week old baby with infant formula, the additional step known as sterilizing – using boiling, chemical or steam methods – is very important to minimize the risk of bacteria making your baby sick. This should continue as long as your baby is drinking infant formula by bottle. It’s not necessary to sterilize breastmilk-feeding equipment, due to the anti-infective qualities naturally found in live milk (unless otherwise directed by your baby’s doctor due to underlying health concerns).

As part of your planning to return to work after parental leave, you might be wondering if you can continue to breastfeed or to partly or fully move to infant formula. Working and breastfeeding is possible and may women find that preparation and planning is the key. You can start this process with our article Returning To Work And Breastfeeding – 8 Tips To Help.

Sleep and Settling

You might wonder if you should make any changes to where or how your baby sleeps, now that he’s three months old. Family, friends or even your doctor or nurse might suggest your baby should be sleeping alone, self-settling, sleeping as much as twelve hours at night or no longer needing breastfeeds during the night. It’s really confusing to hear so much conflicting information and trying to sort fact from opinion.

There’s a lot of outdated information about infant sleep still thought to be true by many people. Add to this the many self-styled sleep experts, “baby whisperers” and others making money from parental uncertainty and it’s really hard to know what will best work for you.

Thankfully, there is a wealth of current, evidence-based research to show us what normal infant sleep patterns look like – and what they don’t. You can access the same qualified practitioners referred to by the BellyBelly team – find them in our article 6 Awesome Baby Sleep Experts Worth Following.

If you’re breastfeeding, another thing people might be quick to tell you is “Your Baby Is Using You Like A Dummy!” and caution you because he breastfeeds to sleep. You might be worried that your baby will never learn to “self soothe” if you always pick him up when he cries, or is worn in a baby sling or carrier for naps. Yet these are two of the few very things actually proven to reduce infant crying.

The most important thing is to do what works best for your family. No matter how many people have opinions on what you should – or shouldn’t – be doing, in the end it’s you and your baby whose opinions matter most. You’re the expert when it comes to your baby.

Play and Development

Your 12 week old baby has mastered holding his head up and can do so for several minutes before tiring during tummy time. He has better arm control and hand eye coordination and might have already achieved his goal of hitting his mobile or play gym toys. Next on his To-Do list is: rolling!

Most babies will first roll from their tummy to their back between 2 and 5 months. They need a bit more upper body control for the next stage, rolling from back onto their side around 4 – 5.5 months and – finally, once they can move their arm and shoulder out of the way, back onto tummy is achieved between 5.5 and 7.5 months. Like everything, these are typical ages and each baby will reach their milestones in their own time.

It’s important your baby gets plenty of floor time every day to work on the muscle and nerve development he needs for rolling. Too much time spent in “containers”, like car seats, infant seats, bouncers, strollers etc. can not only lead to delayed milestones like rolling and crawling but could have ongoing impact for learning and development.

Transport equipment like strollers and car seats should be limited in use to those purposes and infant seats, bouncers, rockers etc. only used for a few minutes each day. Think of the floor as your 12 week old baby’s learning environment and make it the main place he spends his awake time. Time on his back and tummy will help him reach these developmental milestones – and if you need ideas to help him enjoy tummy time, you will find some here: Tummy Time For Baby – How To Make It Fun!

When it comes to breastfeeding, everyone seems ready to share their advice and opinion on how you do it. Yet knowledge about breastfeeding practice and management when you were a baby was at its worst– which might also have been when your doctor or nurse last studied it. Find out what you should ignore in our article, Breastfeeding Advice – 13 Outdated Tips And Advice.

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Yvette O'Dowd has been a breastfeeding counsellor and educator since 1992. She has three adult children and a two year old granddaughter - the best sort of bonus baby! Yvette runs a popular natural parenting network, is a babywearing educator, and runs antenatal breastfeeding classes for parents expecting twins and more! She is a keen photographer and scrap-booker and a keeper of a fairy garden.

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