37^{th week}: The belly overtakes the head

Weeks and days: 36+0 to 36+6
Month: 10
Trimester: 3

The 10th month begins with the 37th week of pregnancy. The fetus gains from about 2,750 to 2,970 grams, and its abdominal circumference becomes larger than its head circumference. A birth up to 36+6 still counts as premature; from 37+0, the baby is considered full term.

around 3 kghow heavy your baby is at the end of the week

Week 37 of 40

Calculate your week

1st trimester2nd trimester3rd trimester

How big and how heavy is the fetus?

318 to 327 mm

By the end of the week, the fetus weighs about 2,970 grams. From head to heel, it measures about 46 centimeters.

Crown-rump length according to the values from Archie et al. 2006, weight according to the WHO growth charts.

This week

Your baby

The lungs are largely mature. Of the babies born now, about 3 out of 100 still have respiratory distress syndrome.
The baby sucks on its fingers and so trains the sucking reflex. After the birth, it can suck and digest breast milk.
The head can now slip into the pelvis. Even so, weeks may still pass before the birth.

Your body

A little urine may leak when you laugh or cough. The pelvic floor muscles loosen for the birth.
Lightening contractions come irregularly, are short, and usually hardly hurt. Labor contractions last 30 to 60 seconds at first and come every 5 to 20 minutes.
After reaching its highest point last week, the uterus sinks a little again.

What matters now

If the baby is lying bottom down, turning it from the outside (external cephalic version) is possible from 36+0. It succeeds in about half of women.
Pack your hospital bag by 37+0. It should include your ID card, maternity record (Mutterpass), and health insurance card, plus your family register or marriage certificate, or, if you are unmarried, your own birth certificate.
If you have another child under 13, you may be entitled to household help in Germany if you have statutory health insurance. Clarify the costs with your health insurance fund in advance, ideally with a doctor's certificate.

Get checked right away: regular contractions before 37+0, your water breaking, bleeding from the vagina, fewer baby movements than usual, severe headache, vision problems, or pain directly below the ribs.

On ultrasound

36+0
Head circumference is on average about 321 mm.
36+0
Abdominal circumference measures on average about 317 mm.
37+0
Abdominal circumference, at about 328 mm, is now larger than the head circumference at about 326 mm.

In Germany, health insurance pays for an ultrasound if the baby is probably in the wrong position, for example before turning. In Austria, the fourth ultrasound is still scheduled up to the 38th week of pregnancy.

Frequently asked questions about the 37th week of pregnancy

Which month is the 37th week of pregnancy?

The first week of the 10th month of pregnancy, in the 3rd trimester. Figures such as 36+4 weeks also belong to the 37th week of pregnancy.

Is my baby still premature in the 37th week of pregnancy?

Yes, up to 36+6, a birth counts as a late preterm birth. About 3 out of 100 of these babies have respiratory distress syndrome at first. From 37+0, the first day of the 38th week of pregnancy, a baby is considered full term.

What does it mean if the head is engaged in the pelvis in the 37th week of pregnancy?

The baby is in position for the birth. Even so, the birth may still be weeks away. In some babies, the head only slips into the pelvis when labor begins.

Is it discharge or amniotic fluid?

Amniotic fluid is clear and pale and sometimes hard to tell apart from urine. If you suspect it, call your midwife or the labor ward. Use a pad, not a tampon, so that the color can be checked. If your water breaks before contractions start, go to the hospital promptly.

Sources

Updated on 31 October 2026 · Fertilio Editorial Team