38 weeks pregnant

How is your baby growing at 38 weeks?

Your baby is ready to enter the outside world, so this week he or she will just be adding weight as fat continues to accumulate, and will perhaps get a little longer. Though the lanugo may have disappeared by now, there might still be some of this fine hair remaining on your baby's shoulders or upper back. Most of the white substance known as vernix should be gone too.

Space is definitely at a premium in the womb but the baby will still be protected by 950ml–1.2 litres of amniotic fluid – it is likely to seem like a lot more if your "waters" break suddenly (this is the amniotic fluid escaping from the womb).

As your pregnancy approaches the final days, changes occur within the placenta and it can no longer work as effectively – this can happen at any time in the next few weeks. When it happens, your baby's pituitary gland will release the hormone oxytocin. The same gland will also release the hormone cortisol. Both of these hormones will cross the placenta and enter your bloodstream.

How are you changing in week 38?

If you weighed yourself last week and again this week, you may notice that your weight has stayed the same – or even decreased. This could mean that, finally, you shouldn't gain any more weight due to pregnancy.

Your body may be preparing for the first stage of labour. However, remember that your estimated due date is just that – an estimate – and few babies are born on their actual due date. You can go into labour any time from now through the next few weeks. When the oxytocin from your baby enters your bloodstream, it will trigger your body to also produce oxytocin, and this hormone will stimulate labour contractions. The cortisol hormone from your baby will alter certain hormones in your body so you produce chemicals known as prostaglandins, which will soften your cervix. For the signs of labour, see week 39.

What you need to know in week 38

You should have an antenatal appointment in week 38 in which your midwife or doctor measures the size of your womb, measures your blood pressure and tests your urine for protein. He or she should also discuss what your options are if your pregnancy goes beyond 41 weeks. If you have any concerns about your labour, don't hesitate to ask questions.

Meanwhile, with labour soon approaching, make sure you have all relevant phone numbers to hand and stay close to home. You or your partner can pack a cool bag with food to keep you and your birth partner going during labour, and don't forget to fully charge your mobile phones, cameras or tablets – you might also want to have plenty of coins for the car park and vending machines.

If you are planning a homebirth, your midwife should advise you how to prepare the room, which includes ensuring that she has adequate light. If you want a clean bed after the birth, you can protect your bedding by covering it with a plastic sheet that is topped with layers of newspaper and a clean old sheet. Your midwife should drop off a pack beforehand with a list of what will be needed.

If a planned (elective) caesarean section is necessary, your antenatal team may choose to perform it in week 38, as long as there are not signs that you are about to go into labour.