Second trimester

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.

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Textbook averages. Individual variation is wide and this is not medical advice — confirm with your OB.