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20 Weeks Pregnant

At 20 weeks pregnant, you're halfway to your due date. Your baby is about 25.6 cm long from head to heel, roughly the length of a banana, and is getting more active each day: kicking, turning and possibly sucking a thumb. A white, greasy coating called vernix now protects the skin. This is the week many people have the detailed anatomy scan, which checks the baby's brain, spine, heart, face, belly and limbs, plus the placenta. For most, the bump is clearly visible now, with the top of the uterus around the belly button. This page covers what the 20-week scan checks, what your belly looks like, when you'll feel movements, and what the halfway point means.

What trimester is 20 weeks?

Week 20 is in the second trimester, which runs from week 13 to week 27 (NHS). It is week 8 of 15 in this trimester, and the third trimester starts at week 28.

  • Week 20 — second trimester, month 5; 20 weeks to go until your due date.
  • Baby's size — about a banana, ~25.6 cm.

Not sure it's 20 weeks? Try our due date calculator.

★ Halfway point — the 20-week anatomy scan.

How big is your baby at 20 weeks?

Size of a

banana

Length, head to heel

~25.6 cm

Weight

~300 g

Up from a mango last week to a banana now.

Baby development at week 20

Halfway there. Measurements now switch from crown-rump to the full head-to-heel length, which is why the figure jumps this week. The fetus is swallowing more, producing meconium (the first stool) in the bowels, and is active with regular sleep-wake cycles. The anatomy scan around now checks growth and organ development in detail. About as long as a banana.

What an ultrasound shows at 20 weeks

The anatomy scan, also called the anomaly or mid-pregnancy scan, is offered to everyone and is ideally done between 18 and 22 weeks. The sonographer looks at the baby's brain and spine, face, heart, belly, kidneys and limbs, measures growth, and checks where the placenta is and how much fluid there is.

If the placenta is lying low, you'll usually be offered another scan later in pregnancy, because it often moves up as the womb grows. Many parents find out the baby's sex at this scan if they ask, though the baby's position doesn't always allow it. The scan can find many physical conditions, but not all of them, so a normal result is reassuring rather than a guarantee.

Your body at 20 weeks

  • Defined, regular baby movements
  • A clearly visible bump
  • Possible heartburn and indigestion
  • Shortness of breath as the uterus rises

Your belly at 20 weeks

At 20 weeks, the top of your uterus usually reaches your belly button. From about now, your provider may measure your bump from the pubic bone to the top of the uterus: the number of centimetres tends to match the number of weeks, give or take 2 cm.

First-time parents often have a small but clear bump by now, while people who have been pregnant before, or are carrying twins, usually look further along. Sharp pains on the side of your belly are common as the womb expands. These are round ligament pains, and they usually ease if you move more slowly.

Tips for week 20

  • The 20-week anatomy scan is a key checkpoint — and often reveals sex if you want to know
  • Eat smaller meals to reduce heartburn
  • Celebrate the halfway mark

20 Weeks Pregnant: your questions

What trimester is 20 weeks?
Week 20 is in the second trimester, which runs from week 13 to week 27 (NHS). It is week 8 of 15 in this trimester, and the third trimester starts at week 28.
How many months is 20 weeks pregnant?
20 weeks pregnant puts you in month 5 of pregnancy. Month 5 covers weeks 18 to 22. Providers count in weeks; months are approximate.
How big is the baby at 20 weeks?
At 20 weeks, the baby is about the size of a banana, roughly 25.6 cm long and around 300 g. That is an average; healthy babies vary.
When will I feel my baby move?
Most people feel first movements between 16 and 24 weeks, and many first-time parents notice them at around 20 weeks. They start as flutters, taps or rolls and get stronger over the coming weeks. If you haven't felt your baby move by 24 weeks, tell your provider so they can check the heartbeat. Once you know your baby's pattern, call straight away if the movements slow down or change.
Is it common to miscarry at 20 weeks?
No, it's uncommon. In the US, a loss before 20 weeks is called a miscarriage, and a loss at 20 weeks or later is called a stillbirth. Stillbirth affects about 1 in 175 births in the US. Call your provider promptly about bleeding, fluid leaking, regular cramps or tightenings, or a change in your baby's movements once you know their pattern.
How much weight should I have gained at 20 weeks pregnant?
It depends on your weight before pregnancy. US guidelines set a total gain range based on your pre-pregnancy BMI, and most of the gain comes in the second and third trimesters. Our pregnancy weight gain calculator shows your own recommended range for each week.
Are there symptoms of a boy or girl at 20 weeks?
No symptom predicts the baby's sex. At this point you don't have to guess: the anatomy scan can usually show the sex if the baby's position allows and you ask. If you'd rather keep it a surprise, tell the sonographer before the scan starts.

Useful at week 20

← All weeks: the full pregnancy week-by-week guide

Sources

Checked against the following public guidance on October 2, 2026. Advice can differ between countries; your doctor, nurse or midwife can apply it to you.