Postpartum Hormone Changes and Your Mental Health in the Fourth Trimester

The first three months after giving birth are often called the fourth trimester. Your body is healing from pregnancy and birth, and adjusting to sleepless nights and the enormous responsibility of caring for a newborn. This is all happening while navigating one of the most significant hormonal shifts your body will ever experience.

If you're feeling overwhelmed, anxious, or depressed during this time, you are not alone. These feelings are not in any way a personal failing. Your body’s hormones are shifting dramatically, affecting your mood, energy, pain levels, and how you experience your body.

This is the reality of postpartum life that isn’t talked about enough. Postpartum demands support for your mental health and for the physical changes happening as you heal. Your mental health and physical health deeply affect each other during recovery. Understanding how they're connected helps you see why addressing both matters equally.

What are postpartum hormonal changes?

During pregnancy, your estrogen and progesterone levels rise dramatically. Quickly following birth and delivery of the placenta, these hormones drop sharply, plummeting below pre-pregnancy levels. This sudden shift is one of the most significant hormonal events your body experiences, and can result in increased anxiety levels.

At the same time, other hormonal changes are taking shape. Levels of prolactin (a pituitary gland hormone that stimulates breastmilk production) surge immediately following birth. Oxytocin, the bonding hormone, is elevated. All of these hormonal systems are interconnected, and when one shifts, so too do others. 

Research shows that these rapid hormonal changes directly impact neurotransmitters in your brain that regulate mood, anxiety, and stress response. What you're experiencing is a massive biological shift as your brain responds to big hormonal changes: postpartum mood changes are not a personal failure.

How do postpartum hormones affect mental health?

The connection between postpartum hormonal changes and mental health is direct and can be significant. Studies confirm that the dramatic drop in estrogen and progesterone after birth increases vulnerability to mood disorders. People with a history of depression or anxiety are at higher risk, but perinatal mood and anxiety disorders can affect anyone.

Postpartum hormonal changes can trigger:

• Postpartum Depression (PPD): characterized by persistent low mood, loss of interest, feelings of worthlessness
• Postpartum anxiety: racing thoughts, excessive worry, panic attacks
• Postpartum Obsessive Compulsive Disorder (PPOCD): characterized by intrusive thoughts, compulsive behaviors
• Postpartum Post-Traumatic Stress Disorder (PPTSD): traumatic memories or flashbacks, accompanied by anxiety, avoidance, hyperarousal or detachment. This can develop after a complicated delivery or traumatic disappointing experience during pregnancy, delivery or postpartum
• Bipolar Mood Disorders: extreme mood episodes (manic or depressive) that can emerge or worsen postpartum.
• Postpartum Psychosis: in rare cases, severe symptoms requiring immediate care

The hormonal piece also matters because it's treatable. Understanding that your mood changes are connected to measurable biological shifts can be the first step toward getting help.

What are signs and symptoms of perinatal mood and anxiety disorders?

Perinatal mental health disorders (encompassing mood and anxiety disorders) include conditions that develop during pregnancy or within the first year postpartum. They're more common than many people realize. Up to 1 in 5 people experience perinatal mood and anxiety disorders, yet many go undiagnosed.

Symptoms of perinatal mental health disorders include:

• Persistent sadness or hopelessness that lasts more than two weeks
• Irritability and anger
• Difficulty bonding with or feeling disconnected from your baby
• Severe anxiety, panic attacks, or racing thoughts
• Loss of interest in things you normally enjoy
• Feeling overwhelmed, unable to cope with daily tasks
• Changes in your sleep patterns (beyond what the baby requires) or appetite
• Upsetting and unwanted thoughts
• Feelings of “craziness” or being “out of control”
• Regret over becoming a parent
• Difficulty concentrating or making decisions
• Thoughts of harming yourself or your baby

If you're experiencing any of these, reach out to your healthcare provider who can help guide you in finding treatment and care. 

If you're in crisis or having thoughts of harming yourself or others, contact the 988 Suicide and Crisis Lifeline (call or text 988) or go to your nearest emergency room.

Baby blues vs. postpartum depression

It's important to understand the difference between the baby blues and postpartum depression, because one is temporary and the other requires treatment.

Baby blues affect roughly 40-80% of new mothers. They typically appear within the first two weeks following birth and resolve on their own within two weeks. Symptoms include mood swings, crying, anxiety, and irritability. Baby blues are common and don't require medical treatment beyond support and rest.

However, it's important to keep an eye on symptoms as baby blues can sometimes develop into postpartum depression.

PPD affects between 1 in 7 people during pregnancy or within the first year after childbirth. It is is characterized by depressive symptoms lasting longer than two weeks that are more severe in nature. They often manifest as persistent sadness, low self-esteem, sleep upsets, anxiety, and difficulties bonding with your baby.

If you’re experiencing these symptoms, talk to your health provider who can help develop a treatment plan.

How are physical health and mental health connected postpartum?

What you do for your body postpartum directly affects your mental health, and vice versa. Treating pain, managing fatigue, and supporting your hormonal system can help improve your emotional wellbeing. At the same time, addressing mental health symptoms also helps you recover physically.

Research confirms that untreated physical pain after birth increases the risk of postpartum depression. One 2008 study examining data from 1,288 postpartum people found those with severe and acute postpartum pain were 3X more likely to have depression than those who had mild postpartum pain.

Common pain symptoms occurring early after giving birth include:

• Cramping in the uterus, abdomen, and or legs
• Pain in the back, neck, or joints
• Pain in the perineum (the area between the vagina and the anus)
• Pain around the cesarean incision (for those who had a C-section)
• Swollen, tender breasts/chests
• Painful hemorrhoids

You may be able to manage many of these symptoms with at-home pain management strategies. However, pain that persists for longer than a few weeks requires evaluation from a specialist to ensure there isn’t a severe physical injury or dysfunction. 

Pelvic floor dysfunction is common after birth, whether you had a vaginal delivery or cesarean section. In fact, roughly 49% of people experience pelvic floor dysfunction during pregnancy or after birth.

Signs and symptoms of pelvic floor dysfunction include

• Urinary issues, including leakage, a sudden urge to pee, difficulty emptying your bladder
• Bowel issues, including leakage of stool or gas, chronic constipation, or feeling of incomplete emptying
• Pain or discomfort in the lower back, hips, pelvis
• Pain during or after sex
• Feeling of heaviness, pressure, or bulging in the pelvis or vagina

Beyond physical injury and muscle dysfunction, postpartum pain can also be connected to the emotional stress and the mental health shifts of the fourth trimester.

This is why a comprehensive care approach matters: physical pain management and mental health support are key parts of the same recovery.

Why screening matters

Most healthcare providers screen for postpartum depression at your 6-week postpartum visit. This screening is important. However, there's typically no screening for physical health issues and how these might be exacerbating, or even causing, postpartum mental health struggles.

At Origin, we understand the connection between physical and mental health. We also know how valuable physical movement can be for improving mental health, and the gaps pelvic floor physical therapy fills when it comes to de-stigmatizing the aspects of postpartum that often lead to feelings of isolation, anxiety, and depression. 

This is why Origin clinicians meet with patients within the first few weeks after birth. During that first appointment, we do a mental health screening, asking about your mood, anxiety levels, and how you're coping emotionally–in addition to assessing your physical recovery.  

One study found that participating in a physical therapist-led program that combined education with specialized exercises reduced the risk for postpartum depression by an astounding 50%. 

Having a physical therapist as part of your postpartum care team can ensure comprehensive postpartum care and support your physical and mental recovery.

Building your postpartum care team

Your postpartum recovery requires more than one type of support. Ideally, your care team includes several of these providers:

• Your OB/GYN, doula, and/or midwife for overall postpartum recovery
• A mental health provider (therapist or psychiatrist) if you're struggling with mood changes or anxiety
• A pelvic floor physical therapist to address physical recovery and pain
• A lactation consultant to address breastfeeding challenges and get support
• Your pediatrician for your baby's health and support

These providers should communicate with each other about your care. You deserve a care team that understands the connection between your physical and mental health.

Where can I get mental health support postpartum?

Building your care team starts with knowing where to look for providers. Here are a few resources and support systems that can help get you started: 

• Postpartum Support International (PSI) provides evidence-based resources, screening tools, and connects you with trained volunteers and professionals who understand perinatal mental health.
• Mavida offers personalized postpartum recovery support, including mental health screenings, medication management, individual, group, and couples therapy, and connection to local resources.
• Seven Starling provides postpartum mental health coaching, support groups, medication management, and expert medical evaluations. Use code ‘Origin’ to receive your first membership month free.

Your healthcare provider can also connect you with a therapist, psychiatrist, or maternal mental health specialist. Treatment for perinatal mood and anxiety disorders is highly effective, whether through therapy, medication, or both.

The bottom line

Postpartum hormonal changes are real, and can profoundly affect your mental health. Thankfully, they're treatable.

If you're struggling with mood changes, anxiety, or depression during the fourth trimester, don’t hesitate to reach out for help.

The difference between simply surviving the fourth trimester and healing is having the right people in your corner. It’s critical to find a care team who can track your physical recovery, mental health, and understand how these two are connected.

Book a visit with an Origin pelvic floor therapist to support your postpartum recovery.

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