Pregnancy and postpartum hormones: A simple guide

• Hormones play a huge role in how you feel during pregnancy and after birth. 

• Emotional ups and downs are normal, but a prolonged low mood is a signal to reach out for support. 

• Simple daily strategies (nutrition, gentle movement, sleep, and self-awareness) can help stabilise your mood. 

• Trust yourself, lean on your support network, and remember: feeling emotional doesn’t mean you’re failing. You’re adjusting to one of life’s biggest changes. 

Pregnancy and the early months of parenthood are a whirlwind, not just for your body but for your emotions too. One minute you might feel elated and glowing; the next, overwhelmed or tearful. This isn’t just in your head, it’s your hormones at work. 

From the first trimester through to the fourth (aka postpartum), hormonal shifts shape how you feel. You might find yourself crying at a TV ad one day, then laughing uncontrollably the next. It’s normal and hormonally driven. 

Understanding these changes can help you feel more in control and less alone. 

First trimester (weeks 1–12) 

• Oestrogen and progesterone: Rise rapidly to support implantation and early pregnancy; can cause fatigue, nausea, and heightened emotions. 
• hCG (Human Chorionic Gonadotropin): Peaks early; helps maintain pregnancy and often contributes to pregnancy nausea and sickness. 
• Mood impact: Emotional swings, irritability, or anxiety are common as your body adjusts. 

Second trimester (weeks 13–26) 

• Oestrogen and progesterone: Continue to rise but stabilise slightly, often leading to more energy and fewer mood swings—the so-called “honeymoon trimester.” 
• Relaxin: Increases to loosen joints and prepare the body for birth. 
• Mood impact: Generally more stable; confidence may rise as morning sickness eases, though emotional changes are still normal. 

Third trimester (weeks 27–40) 

• Oestrogen and progesterone: Peak again to prepare the body for labour and breastfeeding. 
• Cortisol: Rises toward the end of pregnancy, increasing alertness but also fuelling anxiety or irritability. 
• Mood impact: Fatigue, discomfort, and worry about birth can make mood swings more noticeable. 

What happens to hormones after birth? 

Once your baby is born, hormone levels shift rapidly. 

• Oestrogen and progesterone: Drop sharply, which can trigger the “baby blues.” 
• Oxytocin: Surges during birth and breastfeeding, strengthening bonding but also intensifying emotions. 
• Cortisol: May remain elevated, contributing to stress or sleep disturbances. 
• Mood impact: Emotional fluctuations are normal. If sadness, anxiety, or hopelessness continue for more than two weeks, it may signal postpartum depression, something that’s common and treatable with support. 

Emotional changes you might notice 

The combination of physical changes, tiredness, and fluctuating hormones can make even small stressors feel overwhelming. 

It’s common to feel anxious, teary, or unsettled in the third trimester and after birth. Recognising that these feelings have a biological influence can make them easier to manage. 

Baby blues vs. postpartum depression 

Feeling down or tearful in the first two weeks after birth is common. But if low mood, anxiety, or hopelessness lasts beyond two weeks or interferes with daily life, it may be postpartum depression. 

This is not a sign of weakness. Treatment and support are available and effective. 

Look out for: 

• Persistent sadness or emptiness 
• Loss of interest in things you usually enjoy 
• Difficulty bonding with your baby 
• Intense anxiety or panic attacks 

If you recognise these signs, talk to your GP, midwife, or maternal child health nurse. 

Key hormones and how they affect your mood 

Oestrogen: The mood stabiliser 

Helps regulate serotonin, the “feel-good” neurotransmitter. A sharp drop after birth can contribute to low mood and irritability. 

Progesterone: Calming or crashing? 

Usually promotes relaxation, but rapid changes can leave you feeling anxious or unsettled. 

Oxytocin: The bonding hormone 

Supports parent–baby bonding and eases stress. It also amplifies emotions, so both tears and joy may come more easily. 

Cortisol: Stress and energy levels 

Helps your body respond to stress, but too much for too long can fuel anxiety or tension. 

Practical strategies for balance 

Food and drink that support your mood 

Balanced meals and regular hydration stabilise energy and mood. Include protein-rich snacks to steady blood sugar and avoid energy crashes. 

Gentle movement 

Walking, stretching, or yoga can boost endorphins and help regulate hormones. Even five minutes at a time makes a difference. 

Prioritising rest 

Sleep disruptions are inevitable with a newborn. Nap when the baby naps if you can, share night duties, and take rest opportunities whenever possible. 

When extra support matters 

If low mood, anxiety, or overwhelm continues, reach out.  

Postpartum mental health challenges are common and treatable. Lean on your GP, maternal health services, or peer support groups. Support makes a huge difference. 

Listening to yourself and spotting your patterns 

Track your moods, what sets them off, what soothes them, how long do they last? Awareness is powerful. 

You might find tiredness, hunger, or overstimulation trigger certain emotions, while rest, fresh air, or a chat with a friend helps reset you. Over time, these patterns become a guide that strengthens your intuition. 

They remind you that your emotions are real responses to big changes, not weakness or failure. 

You don’t need to do everything perfectly. Focus on what you can realistically manage and accept support when it’s offered. Caring for yourself helps you care for your baby. 

Remember: it’s normal to have ups and downs. Your emotional responses are a sign of your body adjusting, not a reflection of your ability as a parent. 

Sources  

• Emotional Changes in Pregnancy: Hormones & Mood Swings  
• LPFT-Emotional-changes.pdf