What is the 4th Trimester? And Why It's So Important for Moms

Not all new parents have heard of it, but every new mother and their baby will experience it. Learn about the 4th trimester, what to expect and how to prepare.

Giving birth to your baby also brings a great period of change for both you and your baby. As you and your baby adjust to new worlds, it is important to learn about the physical and emotional changes that occur as you welcome your baby to a new life outside of the womb.

This period, also called the 4th trimester, is a 12-week timeframe where you’ll be recovering from your pregnancy. During this time, you’ll also begin learning about your baby’s developmental changes as they transition to a new normal.

Today, you’ll learn about the 4th trimester and what changes to expect for both you and your baby. We’ll also touch on beneficial tips to help you feel your best while recovering.

What is the 4th trimester?

As mentioned, the 4th trimester is the 12-week period that occurs immediately after your baby is born. It begins as soon as your baby enters the world and typically ends when your baby is about 3-months-old. This period is also known as the postpartum period and involves a variety of physical, emotional and developmental changes.

Historically, the term was developed by a pediatrician named Dr. Harvey Karp, who believed that humans are born three months too soon. Dr. Karp theorized that although a fetus’s body is physically ready to come out through the birth canal, their brains are not ready to. Being said, Karp assumed that it takes about 12 weeks for a baby to fully adjust to the outside world.

What occurs during the 4th trimester?

So, what changes should you expect during the 4th trimester? Because the 4th trimester involves many physical, mental and emotional transformations, let’s touch on the important changes you and your baby will most likely experience.

Postpartum changes that you may experience during the 4th trimester:

1. Bodily changes.

Of course, your body will be recovering from giving birth during this time. Because your hormone levels are now changing, your organs begin to shift back into their initial positions. Also, your breast milk is also being developed. This can be uncomfortable for some mothers.

2. Hormonal changes.

As mentioned, your hormones are influx after giving birth. This can bring on many emotional changes, where you may feel things more intensely. Try to remember that this is just a phase and just like your emotions may have shifted during pregnancy, this too shall pass.

3. Postpartum bleeding.

Some new mothers experience bleeding after giving birth. This is completely normal and related to your body healing the perineal area. Should you experience an abnormal amount of bleeding or if it continues, consult with your doctor immediately.

4. Perineal healing.

Your body has just undergone a lot as you’ve worked to bring a miracle into the world. Whether you had a natural birth or a C-section birth, your body will physically recover in time. Typically, this takes up to 6 weeks, however; every mother’s healing process is different and recovery times vary.

5. Breastfeeding changes.

Because your body is undergoing many hormonal changes, your breastfeeding process may not be as easy for some.

6. Fatigue.

Fatigue is normal. Whether you’re experiencing lack of sleep, insomnia and/or emotional ups and downs, this is normal. Your body has undergone a lot of changes and will take a bit for you to adjust back into your normal energy levels. Rest is vital!

Remember, you’re not alone. Millions of mothers give birth daily and everything you’re feeling from the moment you got pregnant to when you gave birth is a lot to take on. You’re strong, look what you and your body have accomplished.

Learn more from St. Louis Children’s Hospital on why the 4th trimester is so important, especially for new mothers:

Major changes that your baby may experience during the 4th trimester:

1. Oversleeping.

Although this is not the case for all newborns, many babies will indulge in long periods of sleep. Once your baby learns how to hold their head up to some degree on their own, these periods of sleep will become shorter. Your baby will begin to notice their surrounding environment and become interested in wanting to explore.

2. Overstimulation and Fussiness.

Your baby became accustomed to a warm and cozy environment in the womb. Being said, it may take some time for your baby to adjust to new bodily positions in addition to having a new place to sleep. This may cause a lot of fussiness which may lead to a lot of crying and lack of sleep for both you and your baby. Your baby may display jerky movements, this is normal as he or she adjusts to their new sleeping environment.

3. Time confusion.

As your baby has spent 9 months in the womb, which is a dark place, it is very likely that your baby will confuse day for night. This is normal and leads to a variety of confusing intervals for feeding and sleeping times. Some babies demand to be fed at all hours of the day and sleep when they please. To avoid more occurrences, try to hold your baby as much as possible to provide that familiar warm and cuddled feeling.

4. Physical changes.

Of course, your baby will begin to grow. Some babies grow more rapidly than others, changing before your eyes! Your baby's arms, legs and feet will begin to unfurl and muscles and many movements will become more noticeable. Let your baby move as they please in order to allow for proper physical and bodily adjustment.

5. Bodily movements.

As mentioned, as your baby begins to grow, more and more movements will become apparent. By 3 months, your baby will be able to push themselves up and have control over their neck movements. Again, let your baby explore and enjoy these milestones.

6. Vision improvements.

As your baby becomes more accustomed to interaction, you’ll notice the development of your baby’s personality. This occurs because your baby’s vision is becoming more enhanced, increasing their need to play, oftentimes seeking more attention.

7. Facial expressions.

You’ll notice smiles and different facial jerks.

As the 4th trimester comes to a close, you’ll have a better idea of your baby’s overall routine. This includes sleeping and feeding schedules as well as predictable fussiness. Overall, your baby will become more familiarized with a consistent sleeping schedule. After enduring all that you have, it is important that you stay present and incorporate healthy coping skills when you’re feeling burnt out. Here are some tips for healthy coping during the 4th trimester.

Tips for coping during the 4th trimester

You’ve made it! Give yourself a pat on the back. As this time brought on a multitude of emotions, let’s keep you feeling good as you continue to recover and transition back into your normal routine.

1. Seek help when needed.

Pregnancy and postpartum is not easy. First, don’t feel as if you need to take on everything by yourself. Ask your partner or a loved one for help, especially if you feel overwhelmed and restless. Take advantage of times when you have visitors. Many friends and family members will offer help. Some will be more excited and focused on meeting your new loved one. Take this time to ask for help (i.e. simple chores, spending time with the baby) so that you can rest. If you foresee a visitor, feel free to ask for groceries. Remember, your loved ones want to support you and asking for help is minimal during your recovery time!

2. Talk to someone if needed.

According to The American Academy of Pediatrics (2021) an estimated 6-22% of new mothers experience postpartum depression. Should not feel like yourself, seek professional help. Talking your stressors out with a professional is one of the best ways to vent, instead of keeping emotions in. You’ll notice that when your hormones transition back to normative levels, you’ll feel better too. This will also help those “baby blues” deplete. Regardless, talking to a professional can help reduce the risk of experiencing postpartum depression. Should you experience more intense thoughts associated to suicide, relate this to a loved one for help. In severe cases, contact 911. Remember, you will get through this! Joining new groups for new moms is also a great alternative. Engaging with new mothers who may be feeling similar to you will bring a sense of ease and comfort.

3. Move.

When you’re feeling better, try to engage in physical activity. Remember to consult with your doctor regarding any intense exercise, as this is typically not recommended during this time. Go for a short walk, stretch, and if you’re up for it - do something you enjoy (i.e. grocery shopping, shopping in general)! Although your main priority is your new baby, it is important to also keep yourself and your mental health in check. Don’t feel guilty about leaving your home and spend some time with yourself.

4. Eat clean.

Pregnancy brought on a lot of cravings. Sometimes, not the most healthy choices and that’s OKAY! Now that your body is entering the final stage of recovery, it is important to treat yourself to healthy and clean foods. This will help with your energy levels and overall mood. Buy veggies, juices, whole grains and lean proteins. Try not to indulge on those delicious snacks as much during this time. However, always treat yourself!

5. Drink water.

Hydration is key throughout any healing process. Make sure you’re drinking plentiful amounts of water everyday so that your body can properly heal and give both you and your baby the energy you need.

6. Sleep.

As is true with eating well and drinking enough water, sleep is vital. Try to catch up on your sleep and maintain a consistent schedule. We all know it is suggested to get 8 hours of sleep a night. Now that you and your baby have become familiar with your new sleeping patterns, it is important to get back into routine so you can feel your best. Resist the urges of cleaning and getting minimal errands done when your baby is sleeping. Take this time to rest as well.

7. Hire a babysitter or night nurse.

Whether you’re a single parent or have a partner, extra help never hurts. When and if you feel comfortable, hire a trustworthy professional to help you around the house and with your little one.

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