Weeks 27–40

Third Trimester

The home stretch

The third trimester is the final push. Your baby is rapidly growing and preparing for life outside the womb. Discomfort increases but so does excitement — you're almost there.

Baby Development Milestones

Wk 28Baby opens eyes, can see light. Brain developing rapidly.
Wk 32Baby is practicing breathing movements. Lungs nearly mature.
Wk 35Baby is gaining about half a pound per week. Most organs fully formed.
Wk 37Officially full term. Baby is ready for birth.
Wk 40Due date! Baby averages 7–8 lbs and 19–21 inches.

Common Symptoms

  • Shortness of breath
  • Frequent urination (again)
  • Heartburn
  • Swollen ankles and feet
  • Pelvic pressure
  • Difficulty sleeping
  • Braxton Hicks contractions
  • Backache

Prenatal Appointments

  • Prenatal visits every 2 weeks (28–36 weeks), then weekly
  • Group B Strep test (35–37 weeks)
  • Non-stress tests if high-risk
  • Cervical checks near due date

Quick Facts

  • Duration: 14 weeks
  • Weeks 27 through 40
  • Months 710 of pregnancy
  • Full term begins at week 37

Tips for the Third Trimester

  1. Pack your hospital bag by week 36
  2. Know the signs of labor — regular contractions, water breaking, bloody show
  3. Install the car seat before your due date
  4. Rest as much as possible
  5. Discuss your birth preferences with your provider

Nutrition in the Third Trimester

By the third trimester, your baby’s growth is at its fastest, and it’s common for appetite, digestion, and comfortable meal sizes to shift again as the growing uterus puts more pressure on the stomach. Many people find smaller, more frequent meals more comfortable than large ones during this stage, and heartburn becomes more common as a result of this physical pressure.

  • Continue your prenatal vitamin through the end of pregnancy — some providers also recommend starting or adjusting iron supplementation in the third trimester depending on bloodwork.
  • Smaller, more frequent meals can ease the heartburn and fullness that often become more pronounced as the uterus takes up more abdominal space.
  • Stay well hydrated — fluid needs remain elevated, and dehydration can contribute to Braxton Hicks contractions.
  • Continue prioritizing protein, iron, and calcium, which remain important for your baby’s rapid growth in the final weeks.
  • Some people find preparing and freezing meals ahead of delivery useful, since appetite and energy for cooking can fluctuate in these final weeks.
  • Continue avoiding alcohol, raw/undercooked proteins, unpasteurized dairy, and high-mercury fish through the end of pregnancy.

Staying Active in the Third Trimester

Exercise in the third trimester often needs to be scaled back in intensity as the belly grows larger and balance becomes more of a factor, but staying appropriately active (if cleared by your provider) can still help with sleep, mood, and physical comfort in these final weeks. Walking and prenatal-specific stretching or yoga are commonly well-tolerated options. Pay attention to your body’s signals more than usual here — this is a stage where providers generally recommend erring toward caution and lower intensity rather than pushing to maintain a pre-pregnancy pace.

For Partners: Supporting the Third Trimester

The final stretch of pregnancy often brings physical discomfort, disrupted sleep, and anticipation (or anxiety) about labor — partners can help by taking on more of the physical tasks around the house, being flexible and present as due-date logistics come together, and learning what to expect during labor so they can be a more active, informed support during delivery. This is also a good time to finalize practical plans together: the route to the hospital or birth center, who to call, and what the first hours after birth might look like.

Frequently Asked Questions

How is this trimester guide different from the week-by-week pregnancy guide?

This page gives you a broader overview of an entire trimester — common symptoms, appointments, and milestones spread across roughly 13 weeks — while the week-by-week guide breaks things down to a single week at a time with more specific detail. Many people use this page to get oriented to a new trimester, then switch to the week-by-week guide for closer tracking as their due date approaches.

What if my symptoms don't match what's listed for this trimester?

The symptoms listed here reflect common patterns for this stage of pregnancy, not a complete or required list — plenty of people experience some of these symptoms earlier, later, more intensely, or not at all, and that's usually within the range of normal. If a specific symptom feels unusual or severe for your situation, it's always worth mentioning to your provider.

Are the baby development milestones on this page exact for every pregnancy?

No — the milestones listed are general developmental patterns based on typical fetal growth, not measurements specific to your baby. Actual development varies within a normal range, and your provider tracks your baby's specific growth through your individual ultrasounds and appointments, which is a more precise way to monitor development than a general milestone list.

Do I need to complete every appointment listed for this trimester?

The appointments listed here reflect commonly recommended prenatal care for this stage, but your specific schedule may vary based on your provider, your health history, and whether your pregnancy is considered higher risk. Always follow the specific appointment schedule your provider recommends for you rather than treating this list as a strict requirement.

When should I be more concerned about symptoms during this trimester?

While many symptoms during any trimester are common and expected, sudden, severe, or unusual symptoms — such as heavy bleeding, severe abdominal pain, sudden swelling, vision changes, or a significant decrease in baby's movement — are always worth contacting your provider about promptly rather than waiting for your next scheduled visit.