First Trimester
Pregnancy Week 4
Your baby is about the size of a poppy seed 🌱 — implantation complete.
Week 4 / 40Week 5
🌱
Size comparison
≈ Poppy seed
Length
0.1 cm
Weight
0 g
Milestone
Implantation complete
About 36 weeks to go until your due date (week 40).
Baby's development at week 4
The fertilised egg has implanted in the uterine wall. The embryonic disc is forming — this tiny cluster of cells contains everything needed to build a human being.
Start prenatal vitamins with folic acid today if you haven't already.
Common symptoms at week 4
Mild crampingLight spotting (implantation bleeding)Breast tendernessFatigue
Eat more of
- ✓Folic acid (leafy greens, fortified cereals)
- ✓Iron-rich foods (lentils, spinach)
- ✓Calcium (dairy, fortified plant milk)
- ✓Vitamin B6 (bananas, avocados)
- ✓Whole grains
Foods to avoid
- ✕Alcohol
- ✕Raw/undercooked meat or fish
- ✕High-mercury fish (shark, swordfish)
- ✕Unpasteurised dairy
- ✕Excess caffeine (>200 mg/day)
- ✕Raw sprouts
Medically reviewed by First OPD Medical Team. Last reviewed on .
Based on average milestones from World Health Organization (WHO), ACOG, NHS UK. Educational only — not a substitute for personalised medical advice.
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