What does "age of viability" mean?

The age of viability (around 24 weeks) is the point at which a baby has a reasonable chance of surviving outside the womb with intensive medical care. Survival rates at 24 weeks are approximately 40-70% with modern neonatal intensive care, though babies born this early face significant health challenges.

When is the glucose screening test?

The glucose screening test for gestational diabetes is typically done between weeks 24-28. You will drink a sweet liquid and have your blood drawn an hour later to check how your body processes sugar. If results are elevated, you will need a longer follow-up test.

Second Trimester 24 weeks pregnant

Pregnancy Week 24 - Viability Milestone & Lungs Developing

At 24 weeks, your baby has reached a major milestone: the age of viability. While still very premature, babies born at 24 weeks have a chance of survival with intensive medical care. The lungs are developing branches and producing surfactant, and your baby is gaining weight steadily.

Corn on the cob

Baby Size

30 cm (head to heel)

Length

600 grams

Weight

Week 24

of 42

Baby Development This Week

This is the age of viability — a significant milestone in your baby's development. The lungs are developing more branches and are beginning to produce surfactant, a substance that keeps the air sacs from collapsing. Your baby's inner ear is fully developed, giving them a sense of balance and position. The face is fully formed with eyelashes, eyebrows, and hair. Your baby is becoming proportionate, though still very lean. The brain is growing rapidly, with billions of neurons forming connections.

Changes in Your Body

Your belly is definitely large now, and you may be experiencing more discomfort. The top of your uterus is about 2 inches above your belly button. You might feel your baby's hiccups regularly. Some women develop gestational diabetes around this time, so your provider may order a glucose screening test. You may experience more frequent Braxton Hicks contractions. Your growing belly can make sleeping uncomfortable, and you may need to use pillows for support.

Common Symptoms at Week 24

Braxton HicksBack painSwellingBaby hiccupsHeartburnTrouble sleeping

Tips for Week 24

Take your glucose screening test if your provider recommends it.
Start stocking up on baby essentials like diapers, wipes, and clothing.
Practice good posture to minimize back pain.
Consider taking a childbirth education class.

When to Call Your Doctor

Seek immediate medical care for signs of preterm labor, preeclampsia (severe headache, vision changes, sudden swelling), heavy bleeding, or significantly decreased fetal movement.

Frequently Asked Questions — Week 24

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