Week 20 of Pregnancy
The halfway mark. The anatomy ultrasound takes a detailed look at every fetal structure.
Fetal size
Banana
- Length
- 16.4 cm
- Crown-rump (CRL)
- Weight
- 300 g
Fetal development
- Measurement switches from crown-rump length to crown-to-heel length.
- Hair starts to grow on the head.
- Swallowing and sucking reflexes develop.
Maternal changes
- The top of the uterus reaches the belly button.
- Typical weight gain so far: 4–6kg.
Recommended checkups
- The 20-week anatomy scan is one of the most important screening exams.
Frequently asked questions this week
-
What does the 20-week anatomy scan check?
It systematically inspects major fetal organs and structures — brain, heart, kidneys, spine, limbs — and also looks at placenta position and amniotic fluid volume. Fetal sex can often be identified, but that is a side observation, not the medical purpose.
Recommended actions this week
- Confirm or schedule the anatomy scan (typically between weeks 19–22).
- Movement patterns become more distinct — note which times of day you feel them most.
Related calculators
Related topics
Jump to week
Textbook averages. Individual variation is wide and this is not medical advice — confirm with your OB.