First trimester
4 Weeks Pregnant
At 4 weeks pregnant (first trimester), your baby is about the size of a poppy seed. Here's what's developing and how you may feel.
Baby this week
size of a Poppy seed
~0.04 in
Week 4
Welcome to week 4. 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 first trimester.
Common symptoms this week
- ›Fatigue
- ›Back ache
- ›Frequent urination
- ›Morning sickness
Ask your provider
- ›Which prenatal vitamin do you recommend for me?
- ›Are any of my current medications a problem during pregnancy?
- ›When is my first ultrasound scheduled — and what should I expect?
For your partner
Energy crash is real and not laziness. Take the dinner shift this week — a small thing that lands big.
This week — to do
- ✓Pick a provider you're comfortable with
- ✓Schedule your first ultrasound
- ✓Start the prenatal vitamin
- ✓Tell people on your timeline, not theirs
Frequently asked — 4 Weeks Pregnant
How big is my baby at 4 weeks?
At 4 weeks, your baby is about the size of a poppy seed — roughly ~0.04 in. Size and growth vary between babies; your provider tracks your baby’s growth at prenatal visits.
How many months is 4 weeks pregnant?
4 weeks is roughly 1 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 symptoms are common at 4 weeks pregnant?
In the first trimester, fatigue, nausea (any time of day), tender breasts, frequent urination, and heightened smell are common as hormones surge. Symptoms vary widely — having few is also normal. Rest, eat small frequent meals, and keep up your prenatal vitamin.
When is my due date if I'm 4 weeks pregnant?
With 36 weeks to go, your estimated due date is about 36 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.
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Week 4
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