24 weeks pregnant
Your baby is about 30 cm and 600 grams; the window for the glucose tolerance test opens.
Week 24 marks the start of weeks 24–28, when screening for gestational diabetes is done. Your baby’s lungs are developing rapidly.
This week’s ultrasound image
Expected ultrasound appearance and measurements at week 24 (illustrative, to-scale drawing).
Abbreviations on the screen
- GS
- Gestational sac diameter
- YS
- Yolk sac
- CRL
- Crown–rump length
- NT
- Nuchal translucency
- BPD
- Biparietal diameter (head width)
- HC
- Head circumference
- AC
- Abdominal circumference
- FL
- Femur (thigh bone) length
- EFW
- Estimated fetal weight
- FHR
- Fetal heart rate (beats per minute)
- GA
- Gestational age (weeks + days)
- UA PI
- Umbilical artery Doppler resistance (PI)
Length (head to heel)
30 cm
Head diameter
60 mm
Head circumference
221 mm
Femur length
44 mm
Estimated weight
600 g
Heart rate
142 bpm
How big is your baby this week?
About the size of an ear of corn
What can be seen on the ultrasound?
BPD is about 60 mm, HC about 221 mm, AC about 199 mm and FL about 44 mm. The estimated weight is around 600 grams.
Your baby’s development
Your baby is about the length of an ear of corn. The lungs start producing surfactant, a substance that makes breathing easier after birth. The face and body are filling out.
Changes in your body
Your womb rises above your belly button. Heartburn, constipation and back pain are common.
Check-ups at this stage
- Glucose tolerance test (OGTT, weeks 24–28)
- Full blood count
- Antibody screening if you are Rh negative
Tips for this week
- Follow your doctor’s fasting instructions before the glucose test
- Keep evening meals light and eat 2–3 hours before bedtime
- Start doing pelvic floor (Kegel) exercises
When should you see your doctor?
Before week 37, regular contractions, lower back pain, pelvic pressure, bleeding or leaking fluid may be signs of preterm labour; contact your doctor.
Growth by week
Values are averages; differences of a few days or a few millimetres between babies are normal.
| Pregnancy weeks | Crown–rump length (cm) | Weight (g) |
|---|---|---|
| Week 4 | — | — |
| Week 5 | — | — |
| Week 6 | 4 mm | — |
| Week 7 | 10 mm | — |
| Week 8 | 16 mm | 1 g |
| Week 9 | 23 mm | 2 g |
| Week 10 | 32 mm | 4 g |
| Week 11 | 43 mm | 8 g |
| Week 12 | 55 mm | 14 g |
| Week 13 | 68 mm | 23 g |
| Week 14 | 85 mm | 43 g |
| Week 15 | 100 mm | 70 g |
| Week 16 | 115 mm | 100 g |
| Week 17 | 128 mm | 140 g |
| Week 18 | 140 mm | 190 g |
| Week 19 | 152 mm | 240 g |
| Week 20 | 25.6 cm | 300 g |
| Week 21 | 26.7 cm | 360 g |
| Week 22 | 27.8 cm | 430 g |
| Week 23 | 28.9 cm | 501 g |
| Week 24 | 30 cm | 600 g |
| Week 25 | 31.9 cm | 660 g |
| Week 26 | 33.8 cm | 760 g |
| Week 27 | 35.6 cm | 875 g |
| Week 28 | 37.5 cm | 1005 g |
| Week 29 | 38.8 cm | 1153 g |
| Week 30 | 40 cm | 1319 g |
| Week 31 | 41.3 cm | 1502 g |
| Week 32 | 42.5 cm | 1702 g |
| Week 33 | 43.6 cm | 1918 g |
| Week 34 | 44.8 cm | 2146 g |
| Week 35 | 45.9 cm | 2383 g |
| Week 36 | 47 cm | 2622 g |
| Week 37 | 48 cm | 2859 g |
| Week 38 | 49 cm | 3083 g |
| Week 39 | 50 cm | 3288 g |
| Week 40 | 51 cm | 3462 g |
Frequently asked questions
What is the glucose tolerance test?
It is a test for gestational diabetes: you drink a sugary liquid and your blood sugar is measured at set intervals. It is usually done between weeks 24 and 28.
Can a baby born at 24 weeks survive?
With neonatal intensive care, some babies born at 24 weeks survive, but the risk of serious health problems is high. Every extra day in the womb helps the baby mature.
Your pregnancy care at SoftCare Clinic
Book an appointment with our specialist doctors for your ultrasound check-up and any questions you may have.
The information on this page is for general guidance only and does not replace a medical examination. Measurements are average values; please discuss your own results with your doctor.
Medical content editor: Op. Dr. Şükrü Sanus