Your Third Trimester: Week-by-Week Changes, Symptoms & What to Expect

You've made it to the final stretch. The third trimester, weeks 28 through 40 (and sometimes 41), is when everything becomes real in the most physical, emotional, and beautiful way possible. Your belly is unmistakably pregnant, your baby is putting on the finishing touches, and your body is working harder than ever to get you both ready for birth.

It's also the trimester that tends to bring the most questions. What's that pulling sensation? Why am I suddenly exhausted again? Is it normal that I can't sleep? The answer to most of those questions is yes, and understanding what's happening week by week makes a real difference.

Here's what to expect from week 28 all the way to your due date.

Key takeaway: The third trimester starts at week 28 and typically ends around week 40-41. It brings significant physical changes, new symptoms, and a lot of emotional preparation. Knowing what's coming helps you feel less blindsided and more in control.

What's Happening to Your Body in the Third Trimester

Before we go week by week, it helps to understand the bigger picture of what your body is going through. The third trimester brings a whole new wave of physical changes, and many of them are directly tied to your baby's rapid growth.

The Return of Fatigue

Remember that bone-deep tiredness from the first trimester? It often comes back. Your body is carrying significantly more weight, your sleep is disrupted, and your organs are working overtime. If you can nap, nap. If you can delegate, delegate.

Swelling and Fluid Retention

Swelling in your hands, ankles, feet, and legs is extremely common in the third trimester. It happens because of decreased blood flow and your body holding onto extra fluid. Mild swelling is normal, but contact your doctor right away if you notice sudden, severe swelling in your face or hands, especially if it's paired with headaches, blurred vision, dizziness, or stomach pain. These can be signs of preeclampsia, which needs immediate attention.

Common Physical Symptoms You'll Likely Experience

For a deeper look at each of these symptoms, including safe remedies and when to call your doctor, see the complete guide to common pregnancy discomforts.

• Heartburn - your growing uterus pushes your stomach upward, making acid reflux worse
• Shortness of breath - your uterus is pressing on your diaphragm, reducing lung capacity
• Back, hip, and pelvic pain - your joints are loosening to prepare for birth, and your shifted center of gravity puts strain on your back
• Varicose veins and hemorrhoids - increased blood volume and uterine pressure on major veins
• Stretch marks - as your skin stretches to accommodate your growing belly, thighs, and breasts
• Tingling or numbness - swelling can compress nerves, especially in the wrists (carpal tunnel syndrome is common in pregnancy)
• Increased vaginal discharge - normal, but call your doctor if you see blood or notice fluid leaking
• Braxton Hicks contractions - irregular, practice contractions that help your uterus prepare for labor

Breast Changes

Your breasts continue to grow, and your nipples may become more sensitive. You might also notice colostrum, a thick yellowish fluid, beginning to leak. This is your baby's first food if you choose to breastfeed, and its presence is a completely normal sign that your body is preparing.

Baby Movement Patterns

You'll feel your baby move throughout the third trimester, though the quality of movement changes as space gets tighter. Big kicks may give way to rolls and wiggles. If you notice a significant decrease in movement at any point, always contact your healthcare provider. It's always worth checking.

Weight Gain

Steady weight gain continues through the third trimester, roughly a pound per week. As you get very close to your due date, weight gain often levels off or even dips slightly. This is normal.

Sleep in the Third Trimester (And Why It's So Hard)

Sleep becomes genuinely difficult in the third trimester, and it's not just because of your belly. There are a lot of factors working against you at once.

Why sleep is disrupted:

• Difficulty finding a comfortable position as your bump grows
• Frequent bathroom trips (your baby is pressing on your bladder)
• Heartburn that worsens when you lie flat
• Leg cramps from the pressure your uterus puts on blood vessels
• Nasal congestion from increased blood flow to mucous membranes
• Restless leg syndrome, which is surprisingly common in pregnancy
• Vivid or strange dreams, especially in the final weeks
• Your baby's movements are waking you up

The best sleeping position: On your left side. This improves circulation for both you and the baby by reducing pressure on the large vein (the inferior vena cava) that runs along the right side of your spine. MRI research has shown that lying supine in late pregnancy causes a 23.7% reduction in blood flow to the uterus and a 6.2% reduction in oxygen transfer across the placenta, compared to lying on the left side. Sleeping on your back becomes uncomfortable anyway as your bump grows, since the baby's weight presses on that same vein and can slow blood flow from your lower body back to your heart.

A few things that genuinely help: a pillow between your knees, a pillow behind your lower back for support, and not eating heavy meals close to bedtime (it makes heartburn worse). If you wake up on your back, don't panic. Just roll back to your left side and go back to sleep.

Week by Week: What to Expect From Week 28 to 41

Each week of the third trimester brings something new. Here's a breakdown of what's happening with your baby and your body as you count down to your due date.

Week 28: Welcome to the Third Trimester

You've officially entered the home stretch. Your prenatal appointments will now shift to every two weeks until week 36. Aim for about 450 extra calories per day to support your baby's growth, and focus on nutrient-dense foods. Sex is generally still safe during a healthy pregnancy, but check in with your provider if you have any concerns.

Your baby: Can open their eyes, detect light, and practice breathing movements with amniotic fluid.

Week 29: Hiccups and To-Do Lists

You may start noticing small, rhythmic movements, not kicks, but your baby hiccupping. It's completely normal and may even play a role in lung maturation. This is also a good week to start working through your third-trimester to-do list: hospital bag, birth plan, car seat installation.

Your baby: Brain development is accelerating rapidly. Fat deposits are building under the skin.

Week 30: Nesting Kicks In

The nesting instinct is real. You may suddenly feel compelled to deep clean, organize, and prepare every corner of your home. Go with it, but pace yourself. Overexerting now will leave you exhausted when you need your energy most.

Your baby: Is about the size of a large cabbage, roughly 15-16 inches long, and gaining about half a pound per week.

Week 31: Chores to Rethink

With nesting in full force, be mindful of what you take on. Avoid moving heavy furniture, using strong chemical cleaners, or climbing ladders. Your center of gravity has shifted significantly, and your joints are looser than usual.

Your baby: Is processing information from all five senses and can recognize your voice.

Week 32: Baby Getting Into Position

Over the next few weeks, your baby will likely move into the head-down position in preparation for birth. About 97% of babies do this on their own. If your baby is breech (bottom-down) at this point, your provider will monitor and may discuss options closer to your due date.

Your baby: Babies born at 32 weeks are considered "moderately preterm" and typically do well with NICU support.

Week 33: More Prenatal Visits, More Monitoring

Prenatal visits are picking up in frequency. Your provider is watching your blood pressure, weight, urine, and baby's position closely. If you're in a high-risk pregnancy, you may be seen even more often. You might also start wondering what happens right after birth. Now is a great time to learn about the immediate postpartum period.

Your baby: Skull bones are still not fully fused, which allows them to compress slightly during delivery.

Week 34: Fundal Height Checks and Maternity Leave Planning

Your provider will measure your fundal height (the distance from your pubic bone to the top of your uterus) at every visit to track your baby's growth. This is also the week to finalize your maternity leave paperwork, write your workplace transition plan, and have any outstanding HR conversations.

Your baby: Vernix (the waxy coating protecting their skin) is thickening. Their central nervous system is maturing.

Week 35: Dropping Into the Pelvis

Your baby may "drop" (engage into your pelvis) around this time. You'll likely feel some relief in your chest as your lungs get more room, but more pressure on your bladder. Expect more frequent bathroom trips. Vivid or strange dreams are also very common at this stage, driven by hormonal shifts and sleep disruptions.

Your baby: Kidneys are fully developed. Most of their major organ systems are ready.

Week 36: Late Preterm Territory

Your prenatal visits will move to weekly from here. Your provider will check your baby's position and may discuss what happens if you go into labor now. A baby born at 36 weeks is considered "late preterm" and has a very good chance of being healthy, though they may need some extra support.

Your baby: Is gaining about an ounce of fat per day. If they're breech, your provider may attempt an external cephalic version (ECV) to manually turn them.

Week 37: Labor Could Happen Any Time

You are not yet "full term" (that's 39 weeks), but labor can begin at any point now. Learn the signs: contractions that become stronger, longer, and more regular; your water breaking; bloody show. Your provider may check your cervix for effacement (thinning) and dilation (opening).

Your baby: Is considered "early term." The lungs and brain are still maturing.

Week 38: Signs of Labor to Watch For

Most women give birth within two weeks of their due date, and week 38 is right in that window. Watch for the signs that labor is approaching: losing your mucus plug, increased pelvic pressure, and contractions that don't go away when you change position or walk around.

Your baby: Is fully formed. The lanugo (fine body hair) is mostly gone. They're swallowing amniotic fluid and practicing breathing.

Week 39: Full Term

Your baby is officially full term. Their organs are fully developed and ready for life outside the womb. If you're having a healthy, uncomplicated pregnancy, your provider may discuss elective induction at 39 weeks as an option. Gentle movement is still encouraged, as long as you have no complications.

Your baby: Is likely around 7 pounds and 20 inches long, though there's a wide range of normal.

Week 40: Your Due Date

Congratulations, you made it to your due date. Only about 5% of babies actually arrive on their exact due date, so don't panic if yours doesn't. Your provider will continue monitoring closely. Natural induction methods like walking are low-risk if you want to try them, though none are proven to reliably trigger labor.

Your baby: Is fully ready. The wait is almost over.

Week 41: If You Go Past Your Due Date

Going past 40 weeks is common and doesn't mean something is wrong. Your provider will likely recommend induction this week if labor hasn't started on its own. Most providers will not allow pregnancy to continue past 42 weeks due to increased risks. Monitoring will be more frequent, including non-stress tests and amniotic fluid checks.

Your baby: May have longer nails, peeling skin, and look a little different than you imagined at first. That's completely normal after birth.

The Emotional Side of the Third Trimester

Nobody talks about this part enough. The third trimester isn't just physically demanding; it's emotionally intense. You're preparing for one of the biggest transitions of your life, and your body is flooded with hormones that amplify everything you feel.

The feelings that come up in these final weeks are often the hardest to admit, because they sit right next to so much love and anticipation.

Claire, 33, describes her last month of pregnancy this way:

"I thought by week 38 I'd feel ready. I'd done the classes, packed the bag, and installed the car seat. But every night I'd lie there on my left side with the pregnancy pillow wedged behind my back, unable to sleep, just running through everything that could go wrong. Not in a rational way. In a 3am way. I kept thinking I should be excited. And I was. But underneath that, there was this quiet terror that I couldn't explain to anyone, because from the outside,e everything was fine. The baby was fine. I was fine. It just didn't feel fine. My midwife asked at one of my weekly appointments how I was doing emotionally, and I started crying before I could answer. She said, " That's exactly the right response for week 38. Your body knows something enormous is coming. Of course, you can't sleep."

That reaction – the coexistence of readiness and fear, love and overwhelm – is one of the most honest things about the third trimester. And it deserves to be named, not managed away.

It's normal to feel excited and terrified at the same time. It's normal to cry over something small and feel fine an hour later. It's normal to feel a sudden surge of love for a person you haven't met yet, and also to feel completely overwhelmed by everything you still need to do.

Common emotional experiences in the third trimester:

• Anxiety about labor and delivery
• Worrying about your baby's health
• Feeling emotionally raw or tearful without an obvious reason
• The "nesting" drive can tip into stress if you push too hard
• Strange, vivid dreams about birth, your baby, or your body
• A mix of impatience (get this baby out) and fear (I'm not ready)

Research bears this out: a study published in MCN: The American Journal of Maternal/Child Nursing found that 27% of women in the third trimester experience moderate-to-severe depression symptoms, often linked to the physical pain that comes with this stage.

These feelings are valid. They don't mean you're not coping well. They mean you're human, and you're about to become a mother.

What actually helps: Staying connected to people who make you feel safe. Focusing on small wins each day rather than the entire to-do list. Talking to your partner, a friend, or a professional about what you're carrying emotionally. And be honest with your care team if anxiety is significantly affecting your quality of life, because support is available and you deserve it. If you want to understand what's happening hormonally and why anxiety tends to spike during this period, this piece on anxiety in women breaks it down clearly.

If the emotional weight of these final weeks feels heavy, you don't have to carry it alone. Soula is an AI-powered mental health app built specifically for women, available 24/7 for those moments when you need support at 2am and don't want to wake anyone up.

Questions to Ask Your Doctor in the Third Trimester

Your prenatal appointments are more frequent now, which means more opportunities to get answers. Don't let the busyness of these visits stop you from asking what's on your mind. If you want a full breakdown of what tests and screenings happen in the third trimester and why, this guide to pregnancy tests by trimester covers everything. Here are some questions worth bringing up:

1. How can I get better sleep? Are there safe sleep aids or supplements I can try?
2. Are there foods I should avoid to reduce heartburn?
3. What are the signs of preeclampsia I should watch for at home?
4. How will I know when I'm actually in labor versus Braxton Hicks contractions?
5. When should I go to the hospital or call you?
6. What is your policy on induction if I go past my due date?
7. Is my baby's position something we need to address?
8. What happens immediately after birth, and what should I expect in the first hours?
9. How long will it take for my body to recover after delivery?

A note on advocating for yourself: If something feels off, trust that instinct and call your provider. You are not being dramatic. Decreased fetal movement, unusual pain, sudden swelling, or anything that feels wrong to you is always worth a phone call.

Frequently Asked Questions About the Third Trimester

When does the third trimester start and end?

The third trimester begins at week 28 of pregnancy and ends at birth, typically around week 40. Some pregnancies extend to week 41 or 42 before labor begins or induction is recommended.

What are the most common symptoms in the third trimester?

The most common symptoms include swelling in the hands, feet, and ankles; back and pelvic pain; heartburn; shortness of breath; frequent urination; Braxton Hicks contractions; fatigue; and difficulty sleeping. Most of these are caused by your growing uterus putting pressure on surrounding organs and structures. Research confirms that women in the third trimester experience an average of 24 distinct symptoms, double the number reported by non-pregnant women of the same age.

Is it normal to feel so tired again in the third trimester?

Yes. Many women experience a return of first-trimester fatigue in the third trimester. Your body is carrying significantly more weight, your sleep is frequently disrupted, and your organs are working harder than usual. A 2023 study analyzing over 1.5 million symptom reports found that sleeping difficulty increases steadily throughout pregnancy, peaking in the third trimester. Rest whenever you can, and don't feel guilty about it.

What sleeping position is safest in the third trimester?

Sleeping on your left side is recommended. It improves blood circulation to your baby and reduces pressure on major blood vessels. Using a pregnancy pillow between your knees and behind your back can make this position more comfortable.

When should I be worried about swelling?

Mild swelling in the feet, ankles, and legs is normal. However, sudden or severe swelling in your face or hands, particularly if accompanied by headaches, blurred vision, dizziness, or abdominal pain, can be a sign of preeclampsia. Contact your doctor immediately if you experience these symptoms.

Is it safe to have sex in the third trimester?

For most women with healthy, uncomplicated pregnancies, sex is safe throughout the third trimester. You may experience some uterine contractions after sex, which is normal. Always check with your provider if you have any concerns or if you've been advised otherwise.

How do I know if I'm in labor or just having Braxton Hicks contractions?

Braxton Hicks contractions are irregular, don't increase in intensity, and often ease when you change position or drink water. True labor contractions become progressively stronger, longer, and more frequent, and don't stop with movement or rest. When in doubt, call your provider.

What does it mean when my baby "drops"?

Baby dropping (also called lightening or engagement) is when your baby moves down into your pelvis in preparation for birth. You may notice less pressure under your ribs and easier breathing, but more pressure on your bladder. It can happen weeks before labor or just hours before.

What is the nesting instinct?

The nesting instinct is a strong urge to clean, organize, and prepare your home for the baby. It's driven by hormonal changes and is completely normal. The key is pacing yourself, avoiding heavy lifting, harsh chemicals, and activities that put you at risk of falling.

What happens if I go past my due date?

Going past 40 weeks is common. Your provider will increase monitoring with non-stress tests and ultrasounds to check on your baby. Most providers recommend induction by 41-42 weeks to avoid complications. Going past your due date does not automatically mean something is wrong.

The third trimester is a lot. It's uncomfortable, it's emotional, it's exciting, and it's exhausting, often all at the same time. But week by week, your body knows what it's doing. Every symptom, every sleepless night, every round of Braxton Hicks is your body preparing for something remarkable.

You're almost there. And when you need a little extra support along the way, whether it's 3am and you can't sleep or you just need someone to talk to, Soula is here for exactly those moments.