The Fourth Trimester is a fairly new term for one of the most difficult parts of pregnancy. But what is it?

By the time I was pregnant with my first, I had been a labor, delivery, and mother-baby nurse, for a couple of years. I knew what to expect throughout pregnancy, labor, and delivery. I knew how I would be taken care of the first two days following the birth of my baby, and how I would follow up with my doctor six weeks later. I felt bulletproof and ready for what lied ahead.

It was 1:15 am when he was finally here. Cries pierced the early June morning. I stared at him for hours as my nurses worked around me, putting me “back together” after the delivery of my first baby boy. 

Me finally meeting my new baby

Around 7 am I finally dozed off for the first time. Thirty minutes later, I awoke to the nurse checking my baby’s temperature and taking my vital signs. Now it was time to breastfeed again. “Oh well,” I thought, “I’ll catch up on sleep eventually.” I had my baby in my arms and the hard part was through. 

Well, not quite. 

Pregnancy and childbirth are hard, and we discount how long it will take to heal and recover from these things. Our days in the birthing center, or hospital, are only the beginning of a fourth trimester journey that will take us months to travel. 

What is the Fourth Trimester of Pregnancy?

The fourth trimester is the term that refers to the first twelve weeks following childbirth. It was first coined by pediatrician, Dr. Harvey Karp, who believes a baby’s environment should be much like it was inside the mother’s womb for the first three months following birth. During this time, you and your baby are separate but still one. It is a time of great change, transition, and process not only in your baby but also in you!

I believe the fourth trimester is the hardest transition we make into motherhood.

Our brain literally changes during pregnancy, birth, and the postpartum period.  It’s not simply a theory that motherhood changes us. It’s science. During this time period, our brains are experiencing “brain plasticity,” where they are reformatting more than they are at any other time in our lives. They are eliminating old connections while facilitating new ones, which may also be part of the reason we are more vulnerable to mental health issues such as postpartum depression and anxiety. And it may be at least one of the reasons that we experience “mommy brain” (also called “placenta brain”). Mommy brain is the term used to describe the way we feel hazy or suddenly forget things.

In other words, there is a good reason we put the milk in the cabinet. 

It isn’t only our brains that are changing by leaps and bounds, it’s also our hormones. Many are dipping. Many are rising, and this will continue for quite some time. Some research even suggests it may take two years for our hormones to settle back into a “normal” pattern.

What is a fourth trimester?

It bothers me enormously that we in the medical community have placed such emphasis on the six-week postpartum visit. I believe it has given mothers a false expectation they should be “back to normal” by this time. But I have good news.

ACOG (The American College of Obstetricians and Gynecologists) is beginning to recognize the importance of the fourth trimester.

Change is coming Mama! There is a better reach of care on the horizon for you, and I couldn’t be happier about it. It is my goal to fan the flames of conversation about the importance of the fourth trimester and to help new mothers make this transition as smoothly as possible through education, encouragement, and community.

Would you like to be a part of this journey? I would love for you to join me and to hear your story as I create resources for new mothers to make a better transition through the fourth trimester. Tell my story. (Don’t worry, it’s completely confidential) Yes, keep me updated on this.

The fourth trimester is a metamorphosis journey. It completely changes us physically, emotionally, and spiritually. Much like the caterpillar that transitions to a butterfly, so are new mothers. New, but still you! Please know you are surrounded by so many others that have gone through what you have, and you are not alone. Here’s to thriving in your fourth trimester journey!

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Rachel is a wife, mother, published author, nurse, childbirth educator, and Spinning Babies® Certified Parent Educator. Rachel's passion is to encourage and empower women in all things related to motherhood.

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