18 Weeks Pregnant
At 18 weeks pregnant (second trimester), your baby is about the size of a bell pepper. Here's what's developing and how you may feel.
Baby this week
size of a Bell pepper
~5.6 in
5.6″
Length
190 g
Weight
22
Weeks to go
📈 Grown +1.0″ since week 16
Average measurements — every baby grows at their own pace.
Welcome to week 18. 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 second trimester.
Common symptoms this week
- Fatigue
- Back ache
- Frequent urination
- Braxton Hicks
Ask your provider
- ›When will I do the glucose tolerance test?
- ›What movement should I be feeling, and when should I worry?
- ›Should I look into childbirth classes — and which ones do you recommend?
For your partner
Come to a prenatal visit if you can. Hearing the heartbeat together changes the whole experience.
This week — to do
- ✓Schedule the 20-week anatomy scan
- ✓Glucose tolerance test (~24–28w)
- ✓Tour your hospital / birth center
- ✓Decide on childbirth classes
Frequently asked — 18 Weeks Pregnant
How big is my baby at 18 weeks?
At 18 weeks, your baby is about the size of a bell pepper — roughly ~5.6 in. Size and growth vary between babies; your provider tracks your baby’s growth at prenatal visits.
How many months is 18 weeks pregnant?
18 weeks is roughly 4 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 expect at 18 weeks pregnant?
The second trimester is usually the most comfortable: nausea and fatigue ease and energy returns. You’ll likely feel first movements between 16 and 22 weeks, and the anatomy scan happens around 18–22 weeks. It’s the ideal window to plan the nursery and research gear.
When is my due date if I'm 18 weeks pregnant?
With 22 weeks to go, your estimated due date is about 22 weeks 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
Sources we consult
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Week 18
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