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Pregnancy · Week 40 Third trimester

40 Weeks Pregnant

At 40 weeks pregnant (third trimester), your baby is about the size of a small pumpkin. Here's what's developing and how you may feel.

Medically reviewed by Jordan Brooks, Certified pediatric sleep consultant· Last updated June 11, 2026

Baby this week

baby is the size of a Small pumpkin

size of a Small pumpkin

~20.2 in, 7.6 lb

🎉 Full term — any day now!

20.2

Length

3.5 kg

Weight

0

Weeks to go

📈 Grown +0.6″ since week 38

Wk 4Week 40Wk 40

Average measurements — every baby grows at their own pace.

Welcome to week 40. Your baby is growing fast and your body is changing. This week we cover development milestones, common symptoms, and what to prepare next as you move through your third trimester.

What's happening

Common symptoms this week

  • Fatigue
  • Back ache
  • Frequent urination
  • Braxton Hicks

Ask your provider

  • What should I bring to the hospital — and when should I leave for it?
  • What are the signs of true labor vs Braxton Hicks?
  • When will you screen me for Group B Strep, and what happens if I'm positive?

For your partner

Practice the hospital route, install the car seat early, and keep your phone charged. You're on call now.

This week — to do

  • Pack the hospital bag
  • Install + check the car seat (CPST if possible)
  • Finish the registry / nursery
  • Pre-register at the hospital
  • Make a birth plan
Frequently asked

Frequently asked — 40 Weeks Pregnant

How big is my baby at 40 weeks?

At 40 weeks, your baby is about the size of a small pumpkin — roughly ~20.2 in, 7.6 lb. Size and growth vary between babies; your provider tracks your baby’s growth at prenatal visits.

How many months is 40 weeks pregnant?

40 weeks is roughly 9 months pregnant. Pregnancy is most precisely tracked in weeks (40 weeks total from your last period), since "months" don’t divide evenly into weeks.

What should I be doing at 40 weeks pregnant?

In the third trimester, monitor your baby’s movements with daily kick counts, attend more frequent prenatal visits, pack your hospital bag by about 36 weeks, install the car seat, and learn the signs of labor. Report decreased movement, bleeding, or signs of preeclampsia to your provider promptly.

When is my due date if I'm 40 weeks pregnant?

You’re at or past 40 weeks. Your provider will monitor you closely and discuss options if labor doesn’t begin on its own. Most providers don’t let a pregnancy continue much past 42 weeks.

References

Sources we consult

We cross-check our editorial guidance against these authorities. Click any source for the original.

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