Second trimester
24 weeks pregnant
The fetus is around the size of a corn cob. Lung development accelerates meaningfully this week, and gestational diabetes screening is commonly offered from now.
Size of
corn cob
Length
30 cm
Weight
600 g
Your baby at 24 weeks
The lungs begin producing surfactant, the substance that allows air sacs to stay open. This is the single most important development for survival outside the womb, and it continues improving right up to term.
The inner ear is fully developed, which gives the fetus a sense of balance and orientation — it now knows whether it is upside down.
Skin is becoming less translucent as fat accumulates beneath it, though it remains wrinkled.
How you may be feeling
The uterus is roughly the size of a football. Back and pelvic discomfort are common, and Braxton Hicks may be more noticeable.
Glucose screening is often offered between now and week 28. It usually involves a sugary drink and a blood test, sometimes with fasting beforehand.
Common symptoms around week 24
- Backache and pelvic discomfort
- Braxton Hicks contractions
- Heartburn
- Swelling in feet and hands
- Leg cramps at night
Appointments and tests around now
Gestational diabetes screening is typically offered between weeks 24 and 28. Gestational diabetes often has no symptoms, which is precisely why it is screened for rather than waited for.
What is normal, and what varies
A gestational diabetes diagnosis is manageable and common. Most cases are controlled with diet and monitoring, and it typically resolves after birth — though it does warrant follow-up afterwards.
Worth doing this week
Do not skip glucose screening
Gestational diabetes is usually symptomless and genuinely matters for both of you. The test is tedious rather than difficult.
Book antenatal classes now if you have not
Most run between weeks 28 and 35 and fill early.
Start tracking movement informally
You are building a sense of your baby’s normal pattern, which is what makes a change detectable later.
Looking ahead
Next week the fetus begins responding more clearly to sound and light.
Nearby weeks
Not sure which week you are in? The week tracker works it out from the first day of your last period, and the due date calculator gives you an estimated due date.