What is the 4th Trimester? It is the period of the first three months of a newborn baby’s development outside the womb. Babies are essentially born 3 months too soon so that they would fit through the mothers birth canal. But they are not developmentally ready for the world.
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When a new parent understands that a newborn really should be treated as if it was still in the womb for a period of 3 months or longer, that baby behaves in a much more contented, calm manner.
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Let’s face it after a woman gives birth to a baby, the postpartum period is an important time of healing for the new mother. When her newborn baby is a content, happy baby, it can make the 4th Trimester/Postpartum period go a lot smoother for the whole family.
Happy Newborn Baby = Happy Postpartum Period = Happy Family
One of the best resources I stumbled upon in preparation for our baby #3 was a book called Happiest Baby on the Block by Dr. Harvey Karp. What he taught about the 4th Trimester made a lot of sense to me. And his tips were SPOT on!
Here are the incredibly helpful lessons learned from the Happiest Baby on the Block and how it worked out for our family with our baby #3.
If you are awaiting your bunding of joy or just gave birth, try these basic principles to keep your baby happy and help keep you mentally healthy while also getting the rest you need to fully heal.
Be willing to be with your baby for 3 months to create the 4th Trimester effect.
Your rest during your postpartum time (12 weeks after giving birth) is crucial to your complete recovery and your health. I probably don’t have to tell you (or maybe I do) how at risk mothers are in the postpartum period/4th Trimester.
This is counterintuitive to how busy we are and the impulse you will feel to get a bunch of stuff done for your baby and the rest of your family.
STOP. It is critical that nobody loses mom. You serve your family best in the months and years to come when you realize how massively important it is for you to fully heal. So many unnecessary complications could be avoided if mom were allowed the opportunity to rest and heal properly.
Massive changes are happening to your body postpartum. Do not ignore your body or force it into extra work.
Make whatever accommodations you have to be able to rest, recharge, care for your baby and your other children postpartum.
If at all possible, do not make commitments to other people or organizations during your 12 weeks of postpartum recovery. Plus you will see that baby needs you during his fourth trimester too.
Happy Baby = Happy Life
Here are 5 helpful hints to help you mimic the environment your baby was accustomed to in your womb. This environment is so helpful to the peaceful development of your baby during the 4th trimester of the 0-3 months of her life.
Babies NEED Noise to Sleep
Believe it or not, you don’t want to tiptoe all day long around your baby and if you have older children in the house that is particularly detrimental to their getting used to having a little monster in the family. Your baby will thrive with a bit of ambient noise around. What you don’t want is sudden startling sounds that will wake her up abruptly.
Your baby was used to the equivalent of vacuum cleaner’s worth of noise when she was in your belly. From all the swooshing of the fluids surrounding her to the gurgling of your stomach to the beating of your heart, your baby is used to a really loud environment and to all of a sudden go from that to absolute quiet is quite jarring for her.
I will tell you that one of the wonders of having my baby make a week stay in the NICU was solidifying the fact that he could sleep through ANYTHING. Alarms, beeps, people talking, other crying babies.
Action item: Pick up one of these White Noise Monitors by Marpac. This thing has saved our lives. It blocks out enough of the teenagers screaming in the distance at each other and yelling down to us on the first floor of the house to keep him in La La Land for the night. Plus it is simulating the noise he associates with pure security and safety, Mother’s womb.
Babies Love Motion
Babies were held, cuddled, jiggled and carried around in motion for 9 months in mama’s womb. Naturally, they love constant jiggling motions. This is why car rides, stroller walks, and swaying arms knock babies out cold.
A baby carrier like a wrap is a great idea to free up your hands while you caress your baby and help him get the sleep he needs.
And one more thing that I wish I could change from raising my first two daughters, I would ditch the swing.
Instead, you “be the swing” for 3 short months. Don’t allow an artificial machine to take the place of a real-life human being holding your baby.
The simple fact is, no living being moves like a plastic swing back and forth or side to side so quickly in the same motion for such a prolonged period of time. It’s ridiculous.
The 4th trimester goes by so quickly. Believe me. You will wonder where the time went. Hold your baby as much as you can. The security and calm you both will feel can be a healing balm for both of you.
This is NOT to say you are the only one who can hold your baby, just that a real live human being should hold your newborn for most of the day. I’ll get to more on that later.
Wrap up that Baby
Swaddling works amazingly on babies to help them sleep. As you can imagine there was not a lot of room to maneuver in your belly. Baby loved being cuddled and the reflexes brought on by flailing arms can startle and wake your child in their sleep.
By wrapping them up, you keep baby secure and warm, and asleep in his bassinet a lot longer. This will help save your sanity friend.
My favorite swaddle blanket is made of a cotton muslin material. My favorites for quality and patterns come from Aden and Anais Silky Soft Swaddle Blanket. 2 years later they still hold up like new and are ridiculously versatile.
When your baby is pushing his arms up and out of the swaddle, give this swaddle sleep sack from Halo a try. My son just now stopped using a sleep sack because they don’t come big enough for him. He loved his sleep sack and I knew he was safely covered at all times no matter how many twists and turns he would make in his crib (when he was 6+ months).
The sleep sacks come in swaddle versions for when they are newborn to regular versions without the swaddle feature for older infants that have control of their arms and may want to extend them over their heads while they sleep. They also come in cotton for warm summer nights and fleece versions perfect for cool New England winters.
Side sleep 
Believe it or not, sleeping on the back may not the favorite position for a baby. If your baby is having trouble on the back, try laying him on his side.
When he is wrapped up in his swaddle, this is easier to do. Give it a try. It may work out great.
Also, here’s a master’s trick, hold your baby in your arms on his side with the side of his face in your palm and the rest of his body supported by your arm. Babies LOVE this “football” hold.
Cuddling doesn’t spoil babies
Cuddling and holding your baby can’t spoil her. Just think, 24/7 was how often your newborn was held when you were carrying her in your womb. If you held her for even 10 hours of the day that is still a drop of nearly 60%! That is a huge change for her.
So pick up your baby and nevermind well-meaning family and friends that will tell you your baby is going to be spoiled.
At least for the first 3 months when she needs your warmth and security to help develop her brain most.
Holding your baby will make nursing that much easier too, as you will notice the hunger signs that much quicker, and prevent her from going into full freak-out mode making latching on that much more difficult.
And by no means do I mean you should not put your baby down to sleep. Absolutely yes! But skip the plastic swing. You really won’t need it, and they are only safe up to 15 pounds. Just about the end of the 4th trimester anyway.
Give baby something to suck
I nursed all three of my children, but there were also given bottles on occasion of breastmilk or very regularly in the beginning, breastmilk+formula with extra calories for my two preemies.
Both my preemies also sucked on a Phillips Advent Soothie Pacifier to calm them. No nipple confusion problems at all.
When my son didn’t need his pacifier anymore and tossed it aside one night in his crib, that was the end of that. That was after the 4th Trimester so I didn’t force it back on him. When he was able to self-soothe to sleep, I knew he didn’t need the pacifier anymore.
But the paci had served its purpose. Something to comfort baby, and fulfill his natural reflex to suck. I provided milk for nourishment, but my boob was not to be a 24-hour paci.
It worked out great in the end.
Enjoy the 4th Trimester
Enjoy the time you make with your baby, it will be gone in a flash.
Can you afford to give your baby 3 months? Can you afford to give your body the 3 months it needs to heal?
Before you know it, your baby will be 3 months old and no longer considered a Newborn, but instead an Infant.
Inhale your sweet baby’s scent (because all too soon, it will change and be gone forever).
Imprint on your mind and heart the face of your baby.
The feel in your arms, and allow yourself to develop and nurture the lifelong love of your new baby.
Congrats and Cheers!
Chandra

Chandra is the chocolate-chip loving mother of 2 teenage girls who started over again with a baby boy in her 40’s! She is the author of The Mom’s Playbook to Conquering Softball Season. She gives other moms the tools they need to prepare their daughters for real life. Her content is centered on helping girls grow up to be well-rounded, equipped, expressive, confident, intelligent, capable, kind and independent.