24 weeks pregnant: symptoms and baby development
A milestone week: the lungs are branching.
Second trimesterMonth 65 min read
By Solesia, from public clinical guidanceUpdated
There is a quiet milestone this week that no one marks with a card. At 24 weeks your baby’s lungs are building the fine branches that will one day carry air, and they have grown enough that, should they arrive early, they would have a real chance with the right care. It is a point many providers treat as the pregnancy changing gear. Their movements are settling into a rhythm of their own, busier after meals and in the evening, and it is worth getting to know. Your appetite is up, the scale is moving more steadily, and feet that are puffy by evening are part of the picture.
How big is your baby at 24 weeks
About the size of an ear of corn
11.8 in long·1.5 lb
Baby development at 24 weeks
At 24 weeks your baby measures about 11.8 inches from head to heel and weighs around 1.5 pounds, roughly an ear of corn. Everything is in proportion; what remains is to grow, to add fat, and to finish the lungs and brain. They gain about six ounces a week from here.
The lungs are the week’s work. The tubes that carry air are branching into finer and finer passages, and at their tips the air sacs are beginning to form. The cells that make surfactant, the substance that will keep those sacs from collapsing when air first enters them, are appearing too. This is why 24 weeks is the threshold it is: the basic equipment for breathing exists, though it is far from ready.
The face is fully formed, with eyelashes, eyebrows and hair on the head, though the color of all three may change after birth. The skin is thin, red and wrinkled because the fat has not arrived yet. The inner ear is complete, so they have a sense of balance and know which way is up when they turn.
Your body at 24 weeks
Feeling hungrier is expected. Your baby is growing fast, your blood volume is high, and your body is storing some fat for breastfeeding. The scale often moves more steadily from now, about a pound a week for a typical starting weight, and that is the pregnancy doing exactly what it should. Snacks with protein in them, fruit, yogurt and nuts, keep hunger even; you do not need many extra calories until the third trimester.
From this week your baby’s movements have a pattern, and learning it is the one habit that matters from here. Notice when in the day they are busy and when they rest. There is no number to reach and no counting to do. The pattern is yours to recognize, and if a day is clearly quieter than your usual, your provider wants to hear about it that day.
Feet and ankles that swell by evening are expected, especially in heat or after standing. The fluid drains overnight. Aches around the ribs, back and lower belly come from the uterus stretching and the joints loosening, and a warm bath, flat shoes and a pillow between your knees are the reliable fixes. Sleep is more broken, and a nap does more than another coffee.
Common pregnancy symptoms at 24 weeks
- Hunger. Fast growth and a high blood volume. Regular meals and protein snacks; no need to double portions.
- Swollen feet. Fluid pooling through the day. Feet up when you sit, and a walk to move it along.
- Rib and back aches. The uterus stretching and joints loosening. Sit tall, warm bath, pillow between the knees.
- Trouble sleeping. Bladder, bump and kicks. Side-lying with pillows, and a nap when you can.
- Stretch marks. Skin stretching over a growing bump. Moisturize for the itch; they fade after birth.
- Hemorrhoids. Pressure on pelvic veins and a slow gut. Fiber, water, and no straining.
- Feeling hot. More blood and a faster metabolism. Light layers, and water within reach.
When to call your provider at 24 weeks
From now, a day with clearly fewer movements than your usual is a same-day call, not a wait-and-see. Your provider would rather check.
Two things are worth a same-day call at any point in pregnancy: bleeding that is more than spotting, and pain that is severe or does not ease. From the second trimester, add fluid leaking and any change in your baby’s usual pattern of movement. You do not need to be sure something is wrong to call; that is what the number is for.
What to do at 24 weeks
- Glucose screening. The window is 24 to 28 weeks. A sweet drink, an hour’s wait, one blood draw; it usually needs no fasting. Many practices pair it with the 24- or 28-week visit.
- Your baby’s pattern. From now, know when they are usually active and when they rest. No counting; the pattern is the thing. A day that is clearly quieter than usual is a same-day call.
- Prenatal visit. One usually lands at 24 weeks: blood pressure, urine, weight, fundal height and the heartbeat. It is the visit to ask about the glucose test and the Tdap shot ahead.
- Birth preferences, first draft. Not a plan, just questions: who you want with you, pain relief you want to know more about, what matters to you. Bring it to a visit and let it change.
Common questions at 24 weeks
What does viability at 24 weeks mean?
That a baby born from this week has a real chance of surviving with intensive care, because the lungs and brain have reached a basic level of readiness. The chances rise sharply with every further week. For nearly everyone this remains a milestone on paper: about nine in ten pregnancies go to 37 weeks or beyond.
How many kicks should I feel at 24 weeks?
There is no set number, and counting to ten is no longer the advice. What matters is your baby’s own pattern: busy times, quiet times, and how the day usually feels. From 24 weeks, if the movements are clearly fewer or weaker than your usual, call your provider the same day rather than waiting to see, whatever the hour.
What happens at the glucose screening test?
You drink a sweet solution with 50 grams of sugar, wait an hour, and have blood drawn to see how your body handled it. Eat normally beforehand unless told otherwise. If the number is high you have a longer, fasting test that takes three hours. Only that second test diagnoses gestational diabetes, which is manageable when found.
Why am I so hungry at 24 weeks?
Your baby is gaining several ounces a week, your blood volume is a third higher, and your body is laying down stores for breastfeeding. Hunger is expected. Regular meals and snacks with protein and fiber steady it; you need only around 300 extra calories a day from the third trimester, so it is more about what than how much.
Written from public clinical guidance, including NHS: Week 24, ACOG: How your baby grows, ACOG: Changes in your body, ACOG: Gestational diabetes, NHS: Your baby’s movements, NHS: Swelling in pregnancy and ACOG: Preterm labor and birth. This page is general information, not medical advice, and does not replace your provider.