39 Weeks Pregnant
At 39 weeks pregnant (third trimester), your baby is about the size of a mini watermelon. Here's what's developing and how you may feel.
Baby this week
size of a Mini watermelon
~20.0 in, 7.3 lb
19.6″
Length
3.1 kg
Weight
1
Weeks to go
📈 Grown +0.9″ since week 36
Average measurements — every baby grows at their own pace.
Welcome to week 39. 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.
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 — 39 Weeks Pregnant
How big is my baby at 39 weeks?
At 39 weeks, your baby is about the size of a mini watermelon — roughly ~20.0 in, 7.3 lb. Size and growth vary between babies; your provider tracks your baby’s growth at prenatal visits.
How many months is 39 weeks pregnant?
39 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 39 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 39 weeks pregnant?
With 1 week to go, your estimated due date is about 1 week away. Due dates are estimates — only about 1 in 20 babies arrive exactly on the date, with most born within two weeks either side.
References
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