Week 4 Size: Poppy Seed
About the size of a tiny poppy seed.
Relative Visual Scale
Solid circle represents your baby's size. Dotted circle shows the full-term week 40 size threshold.
Baby's Development
The blastocyst is now officially an embryo. The cells are organizing into layers: one will form the baby, another the amniotic sac, and the third the placenta.
Weekly Milestones
- ✦ Positive Pregnancy Test Possible
- ✦ Embryo Formation
Your Body & Symptoms
Your missed period is the biggest indicator. A home pregnancy test can likely detect a positive result now. Your uterine lining is enriching to support the embryo.
Common Symptoms this Week
Doctor & Care Recommendations
- ✓ Take a home pregnancy test if your period is late.
- ✓ Schedule your first prenatal appointment (usually set for week 8 to 12).
- ✓ Limit caffeine intake to less than 200mg per day (about one 12oz cup of coffee).
Weekly Health Guides & Resources
First Trimester Guide
Read comprehensive clinical milestones, screening checklists, and developmental guidelines for this phase.
Track & Relieve Symptoms
Learn why symptoms occur, home remedies, and clinical indicators for this week:
Food Safety Checklists
Verify safety statuses, listeria and mercury risks, and safe alternatives for:
Frequently Asked Questions: Week 4
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