20 Weeks Pregnant
At 20 weeks pregnant you are at the halfway mark, and this is the week of the anatomy scan, a head-to-toe ultrasound that checks how the baby is growing and can often reveal the sex. Your baby is about the size of a banana, roughly 9 to 10 inches long and about a pound. Many parents feel the first clear kicks around now, though the exact day varies a lot.
Halfway there. Banana-sized this week, baby is hearing the world through your body — heartbeat, voice, music, all coming through.
25.6 cm length · ~300 g weight
Your week at a glance
| This week | Details |
|---|---|
| Baby size | About a banana, roughly 9 to 10 inches long, about 1 pound |
| What is developing | Senses, taste buds, hair, fine lanugo and waxy vernix coating the skin |
| Your symptoms | First kicks, growing bump, leg cramps, mild back ache, stronger appetite |
| To-do | Have the anatomy scan, decide if you want to know the sex, start a kick log |
You are halfway there
Week 20 sits at the midpoint of a roughly 40-week pregnancy. From here, the focus shifts from early-pregnancy symptoms toward growth, movement, and getting ready for birth. The second trimester is often the steadiest stretch, with more energy and less nausea than the first three months.
Your uterus has reached about the level of your belly button. From this point, your provider will start measuring fundal height, the distance from the pubic bone to the top of the uterus, at each visit to track growth.
The anatomy scan
The mid-pregnancy anatomy scan, sometimes called the 20-week ultrasound, is usually done between 18 and 22 weeks. It takes around 45 minutes and is a detailed, head-to-toe look at the baby. The sonographer checks the brain, spine, face, heart, kidneys, stomach, bladder, arms, legs, hands, and feet, and measures the head, abdomen, and a thigh bone to confirm growth and dates.
The scan also looks at the placenta, the umbilical cord, the amount of amniotic fluid, and your uterus and cervix. If the baby is in a cooperative position, the technician can often see the genitals, so this is the visit where many parents learn the sex if they want to. You can ask the technician to keep it a surprise.
Common symptoms this week
Most are normal signs of a growing bump and shifting center of gravity.
- First noticeable kicks, often felt as flutters, bubbles, or taps low in the belly
- Back ache and round-ligament twinges as the uterus stretches
- Leg cramps, especially at night
- A darker line down the belly and changes in skin pigment
- More appetite now that early nausea has usually eased
A short to-do list
- Confirm your anatomy scan appointment and bring a full or partial bladder if your clinic asks
- Decide ahead of time whether you want to learn the sex
- Start noting when you feel the baby move, so you learn the usual pattern
- Keep taking a prenatal vitamin with folic acid and ask about iron at your next visit
- Drink water and stretch your calves before bed to ease cramps
What the baby is doing now
Inside, the baby is busy. The skin is covered with vernix, a creamy white coating that protects it in the amniotic fluid, and with lanugo, a fine downy hair that helps the vernix stick. Both usually fade before birth. The baby is also swallowing small amounts of fluid, which helps the digestive system practice for life outside.
Sleep and wake cycles are forming, so you may start to notice the baby is more active at certain times of day. There is no need to track this formally yet, but it is the beginning of the pattern you will rely on later when you count movements.
Call your provider if
- Vaginal bleeding or a sudden gush or steady leak of fluid
- Regular, painful tightenings that do not ease with rest (possible preterm labor)
- Severe or constant belly pain rather than brief twinges
- A bad headache, vision changes, or swelling of the face and hands
- Burning when you urinate, fever, or chills
Reflects ACOG mid-pregnancy ultrasound guidance and Mayo Clinic and Cleveland Clinic fetal development references, 2024-2026.
Related questions
- Can you tell the sex at the 20-week scan?
- Often, yes. If the baby is positioned well, the sonographer can usually see the genitals during the anatomy scan and tell you the sex. It is not guaranteed at every scan, since position can hide the view, and you can ask the technician not to look if you want to wait.
- Why can I feel the baby move at 20 weeks?
- By 20 weeks the baby is large and strong enough that movements reach the front of the uterus where you can feel them. Early movements feel like flutters or bubbles. They become more obvious over the next few weeks, and you will start to learn the baby's usual active and quiet times.
- How big is the baby at 20 weeks?
- About 9 to 10 inches long and roughly 1 pound, often compared to a banana. Healthy babies vary in size, so your scan numbers may run a little above or below average and still be perfectly normal.
- What is fundal height and when does it start?
- Fundal height is the distance in centimeters from your pubic bone to the top of your uterus. Providers typically begin measuring it around 20 weeks and at later visits. After about 24 weeks it tends to roughly match the number of weeks of pregnancy, give or take a few centimeters.
Sources & further reading
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App Store Google Play Open Web AppThis article reflects current AAP, CDC, FDA, and other public-health guidance and is for educational purposes only. It does not constitute medical advice. ParentFlow is a wellness companion — not a substitute for your pediatrician. For any medical concern, contact your healthcare provider.