Your Third Trimester at a Glance
Let's be real. The third trimester is a wild ride. You're in the home stretch of this incredible journey, and every week brings something new—sometimes amazing, sometimes... less comfortable. If you're looking for a clear, no-nonsense guide to what's happening in there and how to stay healthy, you've come to the right place. This isn't a medical textbook. It's more like a chat with a friend who's been there, backed up by solid info from the experts.
We're going to walk through the third trimester week by week. We'll talk about your baby's growth, the changes your own body is going through (hello, heartburn and swollen ankles), and the practical steps you need to take to prepare for the big day. Think of it as your roadmap for the final, crucial weeks of a healthy pregnancy.
Weeks 28-29: Hello, Third Trimester!
You've made it! This is the official start of the final act. Your baby is now about the size of a large eggplant, weighing in around 2.5 pounds. Their little eyes can now open and close, and they're starting to develop more defined sleep-wake cycles (which you might feel as periods of intense activity followed by calm).
For you, the reality of the third trimester might start to sink in. You might notice you're getting winded more easily. That's because your growing uterus is pushing up against your diaphragm, leaving less room for your lungs to expand. It's a normal, if annoying, part of the process.
Key Focus for a Healthy Pregnancy: Rhogam & Glucose Screening
Around week 28, your doctor will likely discuss two important things. If you have Rh-negative blood, you'll receive a shot called Rhogam to prevent potential complications. This is standard and crucial. You'll also probably do the one-hour glucose screening test to check for gestational diabetes. It's not the most fun drink you'll ever have, but it's a vital screening for your and your baby's health.
What should you be doing?
- Kick Counts: Start getting into the habit of monitoring your baby's movements. Pick a time when they're usually active (often after a meal) and note how long it takes to feel 10 distinct movements. A consistent pattern is more important than a specific number.
- Preterm Labor Signs: Know the warning signs: regular contractions, pelvic pressure, low backache, or any change in vaginal discharge. Call your provider immediately if you're concerned.
- Nutrition: Your iron needs are high now. Pair iron-rich foods (lean red meat, spinach, lentils) with vitamin C (orange juice, bell peppers) to boost absorption. The American College of Obstetricians and Gynecologists (ACOG) has excellent resources on pregnancy nutrition.
Weeks 30-31: Getting Crowded in There
Your baby is now about the size of a coconut, gaining fat and brainpower rapidly. They're practicing breathing movements, even though there's no air in there yet. You might feel rhythmic, tiny jerks—that's likely hiccups!
Your body is working overtime. Blood volume has peaked, which can lead to more noticeable varicose veins or hemorrhoids. Not glamorous, but common. You might also start experiencing Braxton Hicks contractions—those sporadic, painless tightenings of your uterus. Think of them as practice contractions.
A healthy pregnancy third trimester week by week plan now should include planning. Have you taken a hospital tour? Have you started thinking about your birth preferences? It's a good time to draft a rough plan and discuss it with your partner and provider.
Weeks 32-33: The Nesting Urge (Maybe)
Baby is head-down now (in most cases) and settling into position for birth. Their bones are hardening, except for the skull, which remains soft and pliable for the journey through the birth canal. They're starting to look more like a newborn.
You might find yourself with a sudden burst of energy to clean, organize, and prepare the nursery. That's the nesting instinct. Go with it, but don't overdo it! Listen to your body. On the flip side, you might be too tired to nest at all, and that's perfectly fine too.
Sleep can become a real challenge. Between heartburn, leg cramps, and just finding a comfortable position, you might feel like you're never truly rested.
Weeks 34-35: Almost There
Your baby's lungs are maturing rapidly. If born now, they would very likely do well with a little support. They're shedding most of the fine hair (lanugo) that covered their body and their skin is becoming less red and wrinkled as fat deposits fill out.
For you, the pressure in your pelvis may increase as the baby drops (engages). This is called lightening. It can make breathing easier but increases trips to the bathroom—as if that was even possible. You might also notice more vaginal discharge, which is normal as long as it's not accompanied by itching, burning, or a bad odor.
This is a crucial time in your healthy pregnancy third trimester week by week journey to finalize preparations.
Your 34-35 Week Checklist:
- Install the car seat. Seriously, do it now. Many fire stations offer free checks to ensure it's installed correctly.
- Pack your hospital bag. Include comfort items for you (lip balm, your own pillow, long phone charger), essentials for baby, and something for your birth partner.
- Pre-register at the hospital if required.
- Finalize your maternity leave plans with your employer.
Weeks 36-37: The Countdown is Real
Congratulations! At the start of week 37, your pregnancy is considered "early term." Your baby is now considered full-term by some definitions and is about the size of a head of romaine lettuce. All systems are essentially go.
Your doctor or midwife will likely start checking your cervix for dilation and effacement at your weekly appointments. But don't get too hung up on these numbers—you can walk around for weeks at a few centimeters dilated, or go from zero to baby in a matter of hours. It's not a reliable predictor.
You might lose your mucus plug—a thick, jelly-like discharge that may be tinged with blood. This is a sign your body is prepping, but labor could still be days or even weeks away.
| Common Symptom | Why It Happens | Healthy Ways to Cope |
|---|---|---|
| Swelling (Edema) | Increased blood volume & pressure from uterus on veins. | Elevate feet, drink plenty of water (yes, it helps!), avoid long periods standing/sitting, wear supportive shoes. |
| Heartburn | Progesterone relaxes valve to stomach; uterus crowds stomach. | Eat smaller, more frequent meals. Avoid spicy/greasy foods. Don't lie down right after eating. Ask provider about pregnancy-safe antacids. |
| Back & Pelvic Pain | Shift in center of gravity, relaxin hormone loosening joints. | Prenatal yoga, warm baths, massage, chiropractic care (from a prenatal specialist), use proper posture. |
| Insomnia | Discomfort, anxiety, hormones, frequent urination. | Establish a bedtime routine. Use pillows for support. Limit screens before bed. Practice relaxation techniques. |
I found the swelling in my ankles genuinely shocking one hot week 36 day. My feet looked like they belonged to someone else. My midwife's advice to drink more water seemed counterintuitive, but it actually helped my body release the excess fluid.
Weeks 38-40+: The Final Days
Your baby is now fully developed and just putting on the final ounces of baby fat. Their brain and nervous system are fine-tuning for life outside the womb. You're probably feeling a mix of immense anticipation and a strong desire to just meet them already.
Every little twinge might make you wonder, "Is this it?" False labor (more irregular Braxton Hicks) can be frustrating. True labor contractions typically get longer, stronger, and closer together over time, and they don't go away with rest or a change in position.
The waiting game is tough. Emotionally, you might feel on edge, impatient, or surprisingly calm. All are normal.
Go for gentle walks, watch movies, read books, sleep as much as you can. Your body and baby are working together to decide the perfect birthday.
Frequently Asked Questions (FAQs) About the Third Trimester
Beyond Week 40: The Post-Date Pregnancy
If you pass your due date, try not to stress. Only about 5% of babies are born on their exact due date. Your provider will monitor you and baby closely with tests like non-stress tests (NSTs) and biophysical profiles to ensure everything remains safe. They'll discuss options for induction if you go too far past your due date, usually around 41-42 weeks.
Following a healthy pregnancy third trimester week by week guide gives you knowledge, but it can't predict the exact day. The final lesson of pregnancy is often one of surrendering control—trusting your body, your baby, and your medical team.
The third trimester is a profound physical and emotional marathon. It's okay to be uncomfortable and excited all at once. Use this week-by-week info as a compass, not a strict rulebook. Every pregnancy is unique. Pay attention to your body, communicate openly with your healthcare provider, and know that you are incredibly close to meeting the amazing little person you've been growing all this time.