20 weeks pregnant
Halfway point. This is the week of the anatomy scan — the detailed ultrasound that checks baby's development from head to toe.
Written and reviewed by the babybumpkit editorial team.
What's happening with your baby
At 20 weeks, your baby is about the length of a banana — roughly 25 cm from head to heel — and weighs around 300 grams. Major organ systems are developed enough that the anatomy scan this week can look at them in detail.
Baby's senses are developing fast. Hearing is well-enough developed that they can hear your voice and heartbeat. They have a regular sleep-wake cycle, though it's not synchronized with yours yet.
If you're carrying a girl, all of her egg cells (roughly 6–7 million) have already formed in her ovaries — she will never make more in her life. If you're carrying a boy, the testes have descended into the abdomen.
The anatomy scan
The anatomy scan (also called the level 2 or mid-pregnancy ultrasound) is usually scheduled between 18 and 22 weeks. It's a detailed look at baby's brain, heart, kidneys, spine, limbs, abdominal organs, and more. The sonographer measures key structures to confirm growth is on track.
Most parents also find out the baby's biological sex at this scan, if they want to. The accuracy is very high when the baby cooperates and the sonographer can get a clear view — though sometimes the baby's position prevents a confident call, and you'll be offered a re-check.
The anatomy scan can also detect many structural abnormalities. The majority of pregnancies have completely normal scans. If something is found, your provider will discuss next steps, which may include additional testing or a referral to maternal-fetal medicine.
Common symptoms at 20 weeks
Many people start to feel baby movements ("quickening") around now if they haven't already. First-time parents often notice them between weeks 18 and 22; people with previous pregnancies tend to feel them earlier.
Your bump is now clearly visible. You may be experiencing round ligament pain — a sharp pulling on one or both sides of your lower belly as the ligaments supporting your uterus stretch. It's normal and usually brief.
Other common 20-week symptoms: heartburn, leg cramps, increased appetite, stuffy nose, slight swelling in feet and ankles, and possibly mild back pain as your center of gravity shifts.
What to do this week
Attend your anatomy scan and bring a partner or support person if you can. Many people find this scan emotionally significant — it's often when pregnancy feels most real.
Start thinking about birth-class enrollment. Most classes run 4–8 sessions in the weeks leading up to birth, and they fill up months in advance. Now is a good time to research and book.
If you haven't started a baby registry, this is a typical window to do so — once you know the biological sex (if you wanted to) and after the anatomy scan brings some additional reassurance.
When to call your provider
After 20 weeks, decreased baby movement is something to monitor. Once you're feeling regular movement, a noticeable change — particularly significantly less movement over several hours — warrants a call.
Other reasons to call: vaginal bleeding, sustained severe headaches (especially with vision changes), sudden swelling in your face or hands, or pain that doesn't go away with rest.
Frequently asked questions
Sources and medical references
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