40 Weeks Pregnant

Baby's Development This Week

Your baby is officially full-term and ready to meet the world! About the size of a small pumpkin, they have shed most of their lanugo and vernix. Their lungs are mature and ready for their first breath, and their liver has stored enough starch to turn into glucose after birth. They are likely nestled deep in your pelvis, waiting for the signal that it's time to begin their journey.

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  The baby is fully developed and ready for life outside the womb.
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  Lungs are producing enough surfactant for independent breathing.
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  The skull bones are soft and can mold for passage through the birth canal.
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  The baby has accumulated enough fat for temperature regulation.
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  Antibodies from the placenta provide initial immune protection.
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  About 51.2cm and 3.4kg — the size of a small pumpkin.

Your Symptoms at Week 40

The anticipation is at an all-time high this week. You're likely feeling very heavy and ready to be done, with symptoms like pelvic pressure and frequent 'lightening' as the baby drops lower. Remember that only about 5% of babies arrive on their actual due date, so don't be discouraged if you go a few days past 40 weeks—your baby is just getting those final, finishing touches!

Week 40 Checklist

• ✓Attend your weekly prenatal visit (essential)
• ✓Discuss induction timeline if you go past your due date (essential)
• ✓Stay within a reasonable distance of your hospital (essential)
• ✓Continue kick counts (essential)
• ✓Try to stay calm and patient — your baby will come (recommended)

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.

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  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.
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  Smaller, more frequent meals can ease the heartburn and fullness that often become more pronounced as the uterus takes up more abdominal space.
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  Stay well hydrated — fluid needs remain elevated, and dehydration can contribute to Braxton Hicks contractions.
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  Continue prioritizing protein, iron, and calcium, which remain important for your baby’s rapid growth in the final weeks.
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  Some people find preparing and freezing meals ahead of delivery useful, since appetite and energy for cooking can fluctuate in these final weeks.
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  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