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39 weeks pregnant


Your baby at 39 weeks

Baby at 39 weeks pregnant

At 39 weeks your baby has less and less room, but she is still active, especially when she sees light through your abdominal wall.

  • The amniotic fluid that has been cushioning her in your womb has fallen from 800ml at 32 weeks to 500ml.
  • Your immunity to various infections will have been transferred (as antibodies) through the placenta to your baby and if you go on to breastfeed, then your milk gives your baby more antibodies.
  • Your baby's gums will be quite hard when she's born yet, remarkably, her tooth buds will soon push teeth through them.
  • Her digestive system is ready to try liquid foods.
  • You can try communicating with your baby by playing soothing music when you lie down at night. But there is no evidence that bombarding her with Shakespeare and Mozart will do anything for her development.
  • Your placenta looks like a large discus – it is about 25cm in diameter and a few centimetres thick - an impressive home-grown organ that you should have a quick look at after you've seen your baby. This spaceship-type structure has allowed nutrients and oxygen to get to your baby and taken away her waste products. At term, the placenta will weigh a sixth of your baby's weight. By 42 weeks this brilliant life-support machine can get a bit worn out, which is why babies who go too long overdue are encouraged to come out.

Your body at 39 weeks pregnant

  • Your cervix You may hear your antenatal team talking about how effaced you are or, more precisely, how effaced your cervix is. This is the process by which the cervix gets soft and prepares for the grand opening. After your baby has engaged in the pelvis, she gradually drops closer to the cervix, which reacts by softening, shortening and getting thinner.
  • A show Having a show sounds better than it is. It means that the mucus plug guarding the entrance to the womb has come away. This shows your cervix has been opening up a bit. The mucus plug protected your womb from infections. As your cervix has gone from being long and thick to shorter and softer this dislodges the mucus plug, which comes out as a blob of mucus tinged with blood. It does not mean you are about to start labour but it is one of the hints nature gives you that something will happen soon.
  • Your breasts Your breasts may suddenly at an inconvenient moment spurt out some colostrum. This is the clear fluid that meets all your baby's needs before your proper milk is stimulated to come through by your baby's sucking. It really does have all your baby needs even though it may seem a teeny amount. You have to remember your baby hasn't been knocking back half pint milkshakes in your womb. Nature designed colostrum to be enough, so do not worry.
  • Your waters breaking One in 10 women experience their waters breaking before labour starts, but it can be strangely difficult to tell if the wetness you're sitting in is amniotic fluid or urine. You need to see your antenatal team to find out.
  • Your own maintenance Now is the time to get a haircut - it may be the last chance you get for a while and you will want to look nice in your after-the-birth pictures. Keep up the exercise, be it walking or swimming (with your partner is good). Get some shopping in and do some freezing. See your friends, meet them for tea because even this will be different when your baby is born and for a year, at least, you will struggle to give anyone else your undivided attention.
  • Pain relief Read up about pain relief and ask around making sure you tell women you do not want to hear any horror stories. Know about all sorts of choices from hypnosis to Tens machines, gas and air, and epidurals.

How to respond when people keep asking if you've had the baby yet

This Mumsnetter suggests: "Change your answer phone message to: 'Hello, this is XXXXX. Sorry, I can't get to the phone right now but for those of you ringing with an update, no, I am still sodding pregnant. If anything happens to change that I will update my Facebook/answer phones. Thank you.' Or words to that effect." 



Pregnancy Encyclopedia book coverIllustrations taken from The Pregnancy Encyclopedia, £25, published by DK.

Disclaimer: The information in the pregnancy calendar is for general information and is not intended as a substitute for the medical advice of your own doctor or antenatal team. Not all babies develop at the same time and in the same way, so this week-by-week guide may not always match your own experience. If you have any worries, consult your antenatal team or GP.

Last updated: 3 months ago