28th week: The last week of the 2nd trimester

Weeks and days
27+0 to 27+6
Month
7
Trimester
2

This week, the fetus gains from about 1,040 to 1,190 grams, and the crown-rump length grows to 250 millimeters. It is the last week of the 2nd trimester. If the baby were born now, almost 9 out of 10 premature babies born in this week would survive.

A whole Savoy cabbage with crinkly dark green outer leaves lies on an open hand
Savoy cabbagearound 1.2 kg, the weight of your baby at the end of the week

Week 28 of 40

Calculate your week
1st trimester2nd trimester3rd trimester

How big and how heavy is the fetus?

050100150200250300 mm26th week223 to 23227th week232 to 24228th week242 to 25029th week250 to 259

242 to 250 mm

By the end of the week, the fetus weighs about as much as a Savoy cabbage. From head to heel, it measures about 35 centimeters.

Crown-rump length according to the values from Archie et al. 2006, weight according to the WHO growth charts. A Savoy cabbage weighs 1 to 1.5 kg.

This week

Your baby

  • The skin folds fill with fat, and the baby gets rounder day by day.
  • The lungs could already breathe, but they are not yet mature. They usually only produce enough surfactant toward the end of the 34th to 35th week of pregnancy.
  • The brain grows quickly and gains about 17 grams this week.

Your body

  • Bloating and constipation are common. The baby presses on your stomach, and the hormone progesterone slows down digestion.
  • Many now snore because the lining of the nose swells.
  • Almost one in two pregnant women sleeps poorly, and in the 3rd trimester usually even worse than before.

What matters now

  • If you are Rhesus-negative, an anti-D injection is scheduled in Germany between 27+0 and 29+6. The window begins now.
  • In Germany, the glucose test is only possible until 27+6. In Austria and Switzerland, too, the time window ends now.
  • From next week, it is best to fall asleep on your side; left or right does not matter.

Get checked right away: heavy bleeding, severe or persistent abdominal pain, fever, pain when urinating, or vomiting where you cannot keep anything down.

Gestational sacPlacentaFetus with heartbeat

On ultrasound

  1. 27+0

    Head diameter from temple to temple measures on average about 69 mm.

  2. 27+0

    Thigh bone (femur) measures on average about 50 mm.

  3. 28+0

    Third screening is scheduled in Germany from this day.

In Austria, the third ultrasound follows between the 30th and 34th week of pregnancy. In Switzerland, no routine ultrasound is scheduled in the 3rd trimester.

Frequently asked questions about the 28th week of pregnancy

Which month is the 28th week of pregnancy?

The last week of the 7th month of pregnancy and the last week of the 2nd trimester. The 3rd trimester begins at 28+0, that is, with the 29th week of pregnancy.

Can a baby survive in the 28th week of pregnancy?

Yes, a good one. In England, 88 out of 100 babies who were born in this week and admitted to a neonatal unit survived to discharge.

Is the baby already head down in the 28th week of pregnancy?

Not necessarily. Up to the 28th week of pregnancy, about one in four babies lies bottom down; at the due date, it is only 3 out of 100. The position is checked at every prenatal checkup.

Can I still fly in the 28th week of pregnancy?

Usually, yes. In the UK, according to the NHS, it is the last week in which you can, as a rule, fly without a doctor's certificate. Airline rules vary, so ask beforehand.

Sources

Updated on 30 October 2026 · Fertilio Editorial Team