Week 39 of pregnancy (Days 273-279)

3D Ultrasound image of fetus at 39 weeks.

Baby

39-week babies can weigh up to 3.2kg and be as much as 50cm in length. There can be a large variation in both weight and length at birth. The final growth spurt is now at an end, and there will be little weight gain from now until after birth. Brain development is continuing at a fast pace and this development will continue after birth and for the first 3 years of life.

The vernix, which is the greasy white coating that has been helping to regulate body temperature, continues to shed into the amniotic fluid. The previously clear amniotic fluid will now be tinged a pale milky colour because of it. The outer layer of skin cells are also shedding and being replaced by new skin. At birth, all babies have very pale skin, as the pigmentation is not fully formed. Even babies who will later have dark skin will appear very pale.

Although the bones that make up the skeleton are still hardening, the bones that form the skull remain relatively soft. This makes it possible for them to move, slide over one another and overlap during the birthing process and assists the baby’s passage through the birth canal.

Hair may continue to grow on the head - although some babies may be born with no hair at all – and the fingernails and toenails will now extend beyond the tips of the fingers and toes.

You

You are likely to be continuing to suffer from heartburn and other digestive discomfort. Eating smaller, but more frequent meals can help. It may also help to drink before or after, rather than during meals. This can also help to avoid bloating.

Your cervix will be softening now in preparation for labour. If this is your first baby you will be having weekly antenatal appointments now. For a second or later baby you will be seen less frequently. The cervix may start to dilate a number of hours, days or even a week or two before labour begins and it does not necessarily mean that your labour is imminent. A more definite sign that labour is close is if you pass the mucous plug that seals your cervix.

Symptoms to watch out for

It is normal to be swollen and tired, lacking sleep. There can still be signs of pre-eclampsia and obstetric cholestasis at this time.

Painless Contractions, increasing discharge with bloody show or water breakage are signs that labour may be about to commence. Labour does not begin at a particular point. It begins over time. It is like a plane at the airport going around the taxi ways waiting to go on the runway to take off. It can speed up and slow down before it goes on the runway and finally takes off. It can even speed up and slow down on the runway, several times. Passage of blood mucus or breakage of the waters is contributory evidence to the process become established. It is important not to go to the hospital until the evidence is well developed.

What is routinely offered on NHS

You will be seen at any time by the midwife at this stage. Ideally she can check your cervix at home so that you can aviod going to hospital too early if you think you are in labour.

What other care is available

An additional scan, midwife or consultant opinion can be accessed in a private clinic. There is no need for a referral letter. This can help you with decisions about delivery. You can have more time to discuss. In a private clinic you can have a swab to screen for Group B Streptococcus.

A private one to one birth preparation session is available with a midwife experienced in relaxation techniques for labour, this will be included in your care if you deliver privately.

If you are having a private elective caesarean, this may happen around this time.

At this gestation you are able to book the following scans