Your Third Trimester: A Wellness Guide

Welcome to the Home Stretch

The third trimester spans weeks 28 through 40 (and sometimes a little beyond). Your baby is putting on weight, your belly is growing at a pace that can feel almost surreal, and the finish line is finally, gloriously, in sight. But the final trimester also brings its own set of physical challenges, emotional waves, and logistical to-dos that can feel overwhelming without the right roadmap.

This guide is designed to be that roadmap. Think of it as a practical, warm companion for the weeks ahead, covering everything from easing physical discomfort to nourishing your body, preparing your mind for birth, and understanding what is happening developmentally for your baby.

What Is Happening in Your Body

By week 28, your baby weighs roughly 1 kilogram and is growing fast. Over the next 12 weeks, they will roughly triple in weight. Your uterus, which started the size of a pear, is now pushing up against your diaphragm, squishing your stomach and lungs, which explains a lot of those third-trimester symptoms.

Common physical changes during this period include:

• Braxton Hicks contractions: These practice contractions are your uterus toning up for labour. They are usually irregular and ease with rest or hydration.
• Shortness of breath: As your uterus expands upward, your lungs have less room to expand. This typically improves in the final weeks when the baby "drops" into your pelvis.
• Swelling (oedema): Mild swelling in your feet, ankles, and hands is common. Sudden or severe swelling in your face or hands, however, warrants a call to your midwife or doctor.
• Back and pelvic pain: Relaxin continues to loosen your joints, and the extra weight shifts your centre of gravity, placing new demands on your lower back and pelvis.
• Frequent urination: As baby's head descends, the pressure on your bladder returns with a vengeance.
• Heartburn and indigestion: With your stomach compressed, stomach acid can creep upward more easily.
• Trouble sleeping: A combination of physical discomfort, trips to the bathroom, and an active mind can make restful sleep elusive.

Nutrition in the Third Trimester

Your caloric needs increase slightly in the third trimester. Most guidelines suggest an additional 450 calories per day above your pre-pregnancy baseline, though individual needs vary. More important than counting calories is focusing on nutrient density.

Key Nutrients to Prioritise

Iron: Your blood volume peaks in the third trimester, and iron needs rise to support both your circulation and your baby's developing iron stores. Good sources include lean red meat, lentils, spinach, and fortified cereals. Pairing iron-rich foods with vitamin C helps absorption.

Calcium and Vitamin D: Your baby's bones and teeth are mineralising rapidly. If your intake is insufficient, your body will draw calcium from your own bones. Dairy products, fortified plant milks, sardines with bones, and leafy greens are excellent sources. Vitamin D helps your body use that calcium effectively.

Omega-3 fatty acids (DHA): DHA is critical for fetal brain and eye development, with the most rapid accumulation happening in the third trimester. Research published via the National Institutes of Health confirms that adequate DHA intake during late pregnancy supports infant neurodevelopment. Oily fish (salmon, sardines, mackerel), walnuts, and algae-based supplements are reliable sources.

Fibre: Constipation is common as progesterone slows digestion and baby crowds your digestive tract. Whole grains, fruits, vegetables, and legumes help keep things moving.

Protein: Aim for at least 70-100g of protein daily to support your baby's rapid tissue growth. Eggs, chicken, fish, legumes, Greek yoghurt, and tofu all count.

"In the third trimester, we see the most rapid fetal brain growth of the entire pregnancy. What a mother eats during these weeks genuinely shapes her baby's cognitive foundation."

Dr. Lisa Bodnar, PhD, MPH, RD, Professor of Epidemiology, University of Pittsburgh School of Public Health

Practical Eating Tips When Space Is Tight

With your stomach compressed, large meals can feel deeply uncomfortable. Switch to five or six smaller meals rather than three big ones. Sip water between meals rather than with them to avoid feeling overly full. Keep heartburn at bay by avoiding spicy foods, citrus, and lying down immediately after eating.

Movement and Exercise

Staying active in the third trimester is not only safe for most women, it is genuinely beneficial. The American College of Obstetricians and Gynecologists (ACOG) recommends at least 150 minutes of moderate-intensity aerobic activity per week during pregnancy, unless a healthcare provider advises otherwise.

Exercise in late pregnancy has been shown to reduce the risk of gestational complications, improve sleep, ease back pain, and even shorten labour duration in some studies. The key is choosing the right kinds of movement.

Best Exercise Options in the Third Trimester

• Walking: Gentle, low-impact, and easy to adjust. A 20-30 minute walk daily does wonders for circulation, mood, and pelvic engagement.
• Swimming and water aerobics: The buoyancy of water takes the weight off your joints and spine, making movement far more comfortable at this stage.
• Prenatal yoga: Focuses on breath, gentle flexibility, and stress reduction. Many poses also help encourage optimal baby positioning for birth.
• Pelvic floor exercises: More important than ever. A strong, flexible pelvic floor supports your growing uterus and aids recovery after birth.
• Birthing ball exercises: Sitting and gently rocking on a birthing ball encourages baby into an anterior position and eases pelvic pressure.

Avoid exercises that involve lying flat on your back for extended periods after week 28, as this can compress the vena cava and reduce blood flow. Also avoid contact sports, high-impact activities, and anything with a risk of falls.

Sleep: The Ongoing Battle

By the third trimester, truly restful sleep can feel like a distant memory. A growing belly, frequent bathroom trips, leg cramps, and a busy mind all conspire against you. Yet sleep remains one of the most critical factors in your health and your baby's development.

The National Institute of Child Health and Human Development notes that sleep disturbances are nearly universal in the third trimester and are linked to increased fatigue, mood changes, and even longer labour.

Practical Strategies for Better Sleep

• Sleep on your left side: Left-side lying improves circulation to your kidneys and baby, and reduces pressure on your liver. Use a pregnancy pillow to support your bump, hips, and back simultaneously.
• Elevate the head of your bed: This can reduce heartburn and make breathing a little easier.
• Create a wind-down ritual: A warm (not hot) bath, light stretching, or a relaxation app can signal to your nervous system that it is time to rest.
• Limit fluids in the evening: Reducing how much you drink in the two hours before bed can cut down nighttime bathroom trips without compromising your overall hydration if you drink well during the day.
• Keep a notebook nearby: If your mind races with baby prep to-dos, write them down rather than holding them in your head.

Emotional Wellbeing and Birth Anxiety

It is entirely normal to feel a complex mix of excitement, anxiety, and even grief as you approach the end of pregnancy. Birth anxiety is one of the most common emotional experiences in the third trimester, affecting an estimated 14-22% of pregnant people to a clinically significant degree.

"Fear of childbirth is not irrational. It is a natural response to the unknown. Our job as practitioners is not to dismiss that fear but to meet it with information, preparation, and genuine support."

Dr. Megan Galbally, PhD, MBBS, FRANZCP, Professor of Perinatal Psychiatry, King Edward Memorial Hospital, Perth

If anxiety is interfering with your daily life, sleep, or relationships, please speak to your midwife or GP. Evidence-based options include cognitive behavioural therapy (CBT), mindfulness-based stress reduction (MBSR), and in some cases, medication that is safe during pregnancy.

Preparing Emotionally for Birth

• Take a childbirth education class: Knowledge genuinely reduces fear. Understanding what labour feels like, what to expect physiologically, and what your options are gives you agency.
• Revisit and finalise your birth plan: Not as a rigid script, but as a conversation tool with your care team about your preferences and values.
• Talk about it: With your partner, a trusted friend, your midwife, or a therapist. Verbalising fear often reduces its power.
• Practice mindfulness and breathing: Simple breathwork techniques (like slow, extended exhales) activate the parasympathetic nervous system and are useful both now and in labour.

Preparing for Birth: Practical Steps

The third trimester is the time to shift from planning to doing. Here is a practical checklist to work through in the weeks ahead:

Weeks 28-32

• Attend your gestational diabetes screening if not done yet.
• Begin or finalise your birth plan discussions with your care provider.
• Start researching and booking a childbirth education or antenatal class.
• Begin assembling your hospital bag (even if you are not packing it yet).

Weeks 32-36

• Pack your hospital bag (or home birth kit if planning a home birth).
• Install the infant car seat and have it checked by a certified technician.
• Set up the nursery or sleep space.
• Discuss your postpartum support plan with your partner or support network.
• Attend your Group B Strep swab (usually around week 36).

Weeks 36-40

• Confirm your birth location and how to get there.
• Know the signs of labour and when to call your midwife or head to hospital.
• Rest as much as possible. Your body is doing extraordinary work.
• Prepare some freezer meals or organise postpartum meal support.

Signs to Watch For

While much of the third trimester is simply a matter of getting through the discomforts with grace, some symptoms require prompt attention. Contact your healthcare provider immediately if you experience:

• Sudden or severe swelling, especially in your face or hands
• A severe headache that does not resolve
• Visual disturbances (blurring, seeing spots, or flashes)
• Decreased fetal movement (use your kick count as a baseline)
• Vaginal bleeding beyond light spotting
• A gush or trickle of fluid that may indicate waters breaking
• Regular contractions before 37 weeks
• Severe abdominal pain

These can be signs of conditions such as preeclampsia or preterm labour, both of which are manageable when caught early.

Connecting With Your Baby

The third trimester is also a beautiful time to deepen your prenatal bond. Your baby can hear your voice, respond to light, and even recognise familiar music or stories by late pregnancy. Take time, even just a few minutes each day, to talk to your belly, play music, or simply rest your hands on your bump and breathe.

Kick counting is a meaningful daily ritual that serves double duty: it keeps you connected to your baby's rhythms and gives you an important safety baseline. Most providers recommend counting fetal movements once daily after week 28, aiming to feel at least 10 movements within 2 hours.