You’ve made it halfway through your pregnancy! Week 20 marks a major milestone — and there’s plenty to celebrate, discover, and watch out for. From your anatomy scan to your baby’s size and your growing belly, here’s everything you need to know.

20 week of pregnancy

How Big Is Your Baby at 20 Weeks?

At 20 weeks pregnant, your baby is about the size of a banana or small cantaloupe, measuring around 6.5 inches long from crown to rump and weighing about 10.5 ounces (Mayo Clinic, 2023). The baby is rapidly developing fat stores and becoming more proportionate.

Key Fetal Developments This Week

Your baby is now developing distinct sleep-wake cycles and might even respond to sound. Here’s what’s happening in detail:

  • Nervous system: The brain is developing areas for senses like taste, smell, hearing, and touch.
  • Reproductive organs: An ultrasound will reveal if you’re having a boy or girl (if you want to know!).
  • Skin: Vernix caseosa, a white creamy layer, starts forming to protect baby’s skin from amniotic fluid.
  • Movement: Flutters may now become kicks, rolls, and jabs — known as quickening.

Week 20 Anatomy Scan: What to Expect

One of the most important appointments happens this week: the mid-pregnancy ultrasound, or anatomy scan. Your care provider will assess:

  • Fetal heartbeat
  • Brain and spine development
  • Kidneys, bladder, and stomach
  • Limb length and bone growth
  • Placental placement and amniotic fluid levels
  • Sex organs, if desired

This scan can take 45–60 minutes and may reveal structural or congenital anomalies, though most are simply ruled out at this time.

Common Symptoms at 20 Weeks Pregnant

At the halfway point, many women report feeling more energetic than in the first trimester. However, new symptoms may include:

  • Round ligament pain
  • Backaches
  • Leg cramps
  • Increased vaginal discharge
  • Heartburn
  • Skin changes like linea nigra or darkened nipples
  • Dizziness from changing blood pressure

Your Growing Belly and Weight Gain

Your uterus is at your belly button now, and your bump may start to attract more attention! You’re likely gaining about 1 pound per week — but this can vary.

The average weight gain by 20 weeks is around 10–15 pounds, depending on your pre-pregnancy weight and health.

Emotional Changes and Mental Health

The excitement of reaching the halfway mark can bring relief — but also anxiety. It’s common to feel:

  • More connected to the baby
  • Overwhelmed by upcoming responsibilities
  • Pressure around planning, finances, or birth fears

Don’t hesitate to talk to your provider about your mental well-being or reach out to perinatal mental health professionals if you’re struggling.

Tips for Week 20 of Pregnancy

  • Start your baby registry if you haven’t yet.
  • Hydrate more, especially if you’re experiencing leg cramps.
  • Exercise safely, like walking, prenatal yoga, or swimming.
  • Sleep on your side to support blood flow to the baby.
  • Discuss birthing classes and support groups.
  • Track baby movements and note patterns as they develop.

When to Call Your Doctor

Sometimes there are symptoms that can be concerning. Do not hesitate to get to a doctor as soon as possible! Call your provider if you experience:

  • Severe or persistent abdominal pain
  • Bleeding or unusual discharge
  • No fetal movement by the end of week 20 (especially if you’ve felt it before)
  • Blurred vision or persistent headaches
  • Sudden swelling in hands, face, or feet

Looking Ahead: What Comes Next?

Week 21 brings even more movement from your little one — and possibly your first Braxton Hicks contractions. Your belly will keep expanding and so will your need for comfort, rest, and support.

Academic References (APA Style)