37 to 40 weeks pregnant

At 37 weeks, your pregnancy is considered full-term. You will be meeting your baby over the next few weeks.

The average unborn baby weighs around 3kg to 4kg by now. They are still swallowing amniotic fluid. Experts say that babies at 37 weeks swallow around 450ml of fluid per day.

Their gut (digestive system) now contains meconium - the sticky green substance that'll form your baby's first poo after birth. It may include bits of the lanugo (fine hair) that covered them earlier in pregnancy.

By 38 weeks the umbilical cord will be about 50cm to 60cm long. Your baby's heart and circulatory system (the blood vessels that carry blood to and from the heart) are fully formed.

In the last weeks of pregnancy, your baby's head should move down into your pelvis. You might notice your bump move downwards. Sometimes this does not happen until labour starts.

The fine hair that covered your baby's body is now almost all gone. But some babies may have small patches of it when they're born.

Because of the hormones in your body, the baby's genitals may look swollen when she or he is born. But they'll soon settle down to their normal size.

At this stage, they are ready to be born.

Pregnancy normally lasts about 40 weeks - that's around 280 days from the first day of your last period. Labour usually starts a week either side of this date, but you might go overdue.

Page last reviewed: 23 September 2022
Next review due: 23 September 2025