What happens at the 20-week anatomy scan?

The anatomy scan is a detailed ultrasound that checks your baby's growth, organ development, and overall health. The technician will examine the brain, heart, spine, limbs, and other structures. They will also check the placenta position and amniotic fluid levels. This scan can often reveal your baby's sex if you wish to know.

What are Braxton Hicks contractions?

Braxton Hicks are "practice" contractions that feel like a tightening or hardening of your uterus. They are usually painless, irregular, and stop when you change positions or drink water. True labor contractions, by contrast, become regular, more frequent, and increasingly intense.

Second Trimester 20 weeks pregnant

Pregnancy Week 20 - Halfway There! Anatomy Scan Ultrasound

Congratulations — you are halfway through your pregnancy! At 20 weeks, your baby is about the size of a banana. This is typically when you have your anatomy scan ultrasound, a detailed examination of your baby's development. You are likely feeling regular movements now.

Banana

Baby Size

16.4 cm

Length

300 grams

Weight

Week 20

of 42

Baby Development This Week

Your baby is developing a sleep-wake cycle and you may notice patterns of activity and rest. The anatomy scan around this time will check your baby's organs, growth, and development in detail. Your baby is producing meconium in the intestines. If you are having a girl, her uterus is fully formed. If a boy, his testicles are beginning to descend. Your baby's skin is thickening and developing layers under the vernix.

Changes in Your Body

Your belly is definitely showing, and your uterus has reached your belly button. You are likely feeling regular baby movements. Some women experience shortness of breath as the uterus presses against the lungs. You might have trouble sleeping, and heartburn is common as the uterus pushes against your stomach. Your hair may be thicker and shinier due to hormones that slow hair loss. You may start to feel Braxton Hicks contractions — practice contractions that are usually painless.

Common Symptoms at Week 20

Regular baby movementsShortness of breathHeartburnBraxton Hicks contractionsThicker hairSwelling in legs

Tips for Week 20

Prepare questions for your anatomy scan ultrasound appointment.
Start doing perineal massage to help prepare for delivery.
Take a daily walk to help with circulation and mood.
Keep a kick count chart if your healthcare provider recommends it.

When to Call Your Doctor

Contact your provider immediately for severe headache, vision changes, sudden swelling, painful contractions, decreased fetal movement, or any bleeding.

Frequently Asked Questions — Week 20

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