Author: TLN

A complete guide to the fourth trimester

Pregnancy brings many of its own surprises. Whether you’re expecting your first child or your fifth, the experience is completely different every single time. And it’s easy to be so caught up in just getting through those nine months that you forget all about the fourth trimester. 

No, you won’t be pregnant for twelve months (although sometimes it feels like it!). The fourth trimester is a nickname given to the time immediately postpartum. And although the birthing parent isn’t pregnant anymore, this phase is crucial to both parent and child development. Keep reading for the ins and outs of what the fourth trimester is, why it matters, and what to expect in those precious early days with your baby.

What is the fourth trimester?

The fourth trimester of pregnancy actually doesn’t refer to pregnancy at all, but to the twelve-week period right after delivery. It’s called a “fourth trimester” because during this time, your baby is still adapting to life outside of the womb. During this adjustment period, infants will need a lot of close physical contact with their parents.  

This theory originated from Dr. Harvey Karp in 2002 as a way of explaining and understanding the needs of human infants after birth. The idea is that (in order to allow our heads and their relatively large brains to pass through the birth canal) humans are born about three months early. And that makes sense. After all, we’re much less capable at birth than, say, horses — who can gallop about 24 hours after they’re born. By contrast, it takes human babies an average of 12 months to take their first steps. 

In order to provide the most comforting and supportive environment for a new baby, Karp recommends recreating the womb as much as you can. That means soft and varied noise, gently restricted movement, and staying as close to the mother’s body as possible. 

When does the 4th trimester end?

The fourth trimester runs for 12 weeks, or until your child is about three months old. After that time, you’ll likely start to see clear signs that your baby is starting to make their way out of the newborn phase and start engaging with the world around them. You’ll notice them beginning to lift their head, turning toward sounds, smiling, showing preferences for certain people, and even starting to coo. 

Of course, every baby is different and hits these milestones at different times. Pediatric appointments are usually scheduled at regular intervals throughout the fourth trimester. Working with an International Board Certified Lactation Consultant (IBCLC) can help you ensure your child is gaining enough weight and that your feeding routine is working well for both of you. If you have any concerns about your child’s development, don’t hesitate to reach out to a professional for support. 

What does the fourth trimester mean for parents?

Although the term “fourth trimester” refers to the baby’s development, it also kind of alludes to another three months of pregnancy — a good reminder that both parents and babies learn to navigate this new stage of life together. The parent’s (and family’s) development is no less important than the child’s. And this can be extremely helpful for parents to keep in mind, especially if they don’t know what to expect postpartum.  

During this time, new parents aren’t just getting used to caring for a child. Their bodies are going through a recovery process. The resulting physical discomfort and hormonal changes can trigger a rollercoaster of emotions. These might include anxiety after childbirth or difficulty bonding with your child. A new parent can feel frustrated, overwhelmed, and sad. All of this is normal and pretty common. But that doesn’t mean that you have to go through it alone.  

According to the Centers for Disease Control and Prevention (CDC), about 1 in 8 mothers experience postpartum depression. If you’re feeling the baby blues persistently, you can and should reach out for immediate support or receive more information from Postpartum Support International as a useful resource. Your mental health is a vital part of your overall well-being, and having trusted resources for medical care is a key part of building your support system.  

When should I see my IBCLC, doctor, or midwife?

Seeking help when needed is a sign of strength, and it’s the best way to ensure your entire family’s well-being. Here’s a list of some moments when it may be helpful to reach out for additional support:

Postpartum visits 

Typically, the birthing parent will have a postpartum checkup at 6 weeks after delivery. This is a great time to check in with your doctor about how your recovery is going. You can ask for an appointment sooner, or a second postpartum visit if new questions arise. 

Mental health and well-being

Your doctor will ask questions related to your mental health after pregnancy. These are designed to screen for any postpartum mental health disorders, like postpartum depression or postpartum anxiety. It’s a good idea to be honest about how you’re feeling and any concerns you may have. Your medical team is genuinely interested in your well-being, and they’ll want to know if you’re feeling down or anxious after birth. There are many ways that a professional can treat postpartum mental health conditions — but they won’t be able to help unless you let them know how you feel. If you don’t feel comfortable sharing with your doctor, you should find a therapist you feel safe with.

Starting a new routine

Your body has just been through a major event, and it needs time and care to heal. Postpartum recovery exercises are also an important part of the fourth trimester. Gentle exercises and movements, such as pelvic floor exercises and gentle stretching, can aid in the healing process. Of course, you’ll want to check in with your healthcare provider before starting an exercise routine. 

IBCLCs can help you navigate other shifts to your routine, like returning to work. If you’re worried about maintaining your milk supply while being away from your little one, set up a consultation

When to see an IBCLC

One thing that surprises many new parents is that breastfeeding — often referred to as “the most natural thing in the world” — doesn’t come easily to many parents or babies. Like any new skill, breastfeeding has to be learned. And that generally comes with some early frustrations, fumbles, and discomfort. These can be compounded when you’re unsure of where to go for help, or convinced that you should “know what you’re doing” in the first place. 

Reaching out for lactation care doesn’t have to be stressful or expensive. Many parents can qualify for free or low-cost lactation support through their health insurance plans. Once they reach out for a free consultation, TLN handles the back-and-forth with insurance, so that nursing parents have one less thing to worry about — and can focus on caring for their families.  

An IBCLC works with you and your child to help meet your feeding goals. An IBCLC plays an important and singular role. IBCLCs are the highest accredited healthcare professionals specializing in lactation and function as a bridge between obstetricians and parents as well as pediatricians and babies — caring for both parent and child during a really challenging, vulnerable time. 

While there are many benefits to breastfeeding, one of the most important is the relationship it builds between the parent and child — and IBCLCs play a vital role in empowering that relationship. Here are a few common instances where meeting with an IBCLC is often helpful: 

Latching issues

One common challenge new parents face when it comes to breastfeeding is latching issues. It’s normal for you and your baby to need time to figure out the best positioning and technique for a good latch (that’s not painful!). An IBCLC can provide you with valuable tips and tricks to make this process less stressful for you and your baby. If there is a latching issue, they can help diagnose and work with you to remedy it. 

Low milk supply 

Low milk supply is a common concern that can create a lot of stress in new parents. It’s important to remember an important factor in establishing milk supply is supply and demand. If you or baby are removing breastmilk effectively from your breasts 8-12 times every 24 hours, your body will most likely establish a healthy milk supply. Low milk supply is often a perception issue. If you’re concerned about your milk supply, try contacting a lactation consultant about techniques and strategies to increase your supply.

Dealing with medical concerns  

IBCLCs can help you navigate both major and minor breastfeeding issues. This could include clogged ducts, mastitis, thrush, and cracked nipples — and unsurprisingly, a painful nursing experience is also likely to be a short one. An IBCLC can help you manage these concerns before they become a reason to give up on breastfeeding and pumping altogether.  


Breastfeeding is physically demanding and sometimes uncomfortable, especially in the early weeks. It’s important to take care of yourself during this time. Make sure you’re getting as much rest as possible, staying hydrated, and getting in three meals (or lots of snacks), and asking for support when needed. An IBCLC can help you identify what you need to stay healthy, comfortable, and empowered as you make the choices that make sense for your family.  

Dealing with advice overload  

Feeding your child is a necessity, and access to the care you need to do that is a human right. You may find, however, that the act of feeding your baby (however you do it) evokes strong opinions and emotions in others.  

Every breastfeeding journey is unique, and what works for one person may not work for another. Trusting your instincts and seeking support when needed can help you filter through the noise — and bring the focus back to what really matters.  

As you enter parenthood, it’s important to remember that the day your baby is born is truly just the beginning of the journey. And as the proverb goes, “If you want to go fast, go alone. If you want to go far, go together.” The period after birth is a time of immense change and adjustment as you navigate the new world of parenthood, and your personal and clinical support system will help you through. 

Understanding the fourth trimester — both what it looks like, and when to ask for help — is key to providing the best care for both you and your baby. 

Get the care you deserve

We’re here for you, every step of the way. We work with your insurance to provide in-home, in-office, or telehealth visits with an IBCLC.