Only a few weeks to go… how exciting! If you’re wondering what’s going to happen to your body and your fast-growing baby during the last segment of your pregnancy, here’s what to expect in the third trimester.
What to expect in the third trimester
Let’s go through the basics first. When does your third trimester actually begin? It starts around the 28 week mark and lasts until the birth itself, so in total it’s about 13 weeks. Plenty of babies stay inside past the 40 week mark. If you haven’t given birth by week 41 or 42 you will probably be overdue and your doctor might recommend inducing labour.
What symptoms will I get in my third trimester?
Look out for lots more activity from your baby as they grow and change, and as your body responds to the changes.
- Nausea or morning sickness often goes away after the first trimester but if you’re having twins – or more! – it can stick around until you give birth
- Headaches can be triggered by a lack of sleep, smells, stress, being too hot and more. Regular meals, exercise and sleep routine should help, along with time to chill and smell the coffee
What happens to the baby in the third trimester?
- In the third trimester your baby’s brain grows even faster
- Your baby grows a lot, from around 2.5 pounds and 16 inches long in week 28 to 6-9 pounds and as long as 22 inches in week 40
- Baby cartilage turns into bone in months 7-8, so eat lots of calcium-rich foods
- By week 32 their skin becomes opaque
- Week 36 sees fat continuing to accumulate as your baby sheds vernix, the waxy covering that protects their skin from your amniotic fluid
- They also shed their lanugo, a warm furry coat
- In the last few weeks the baby’s first poo, called meconium, starts to build up inside them
- By week 29-30 their touch receptors are fully developed and they can get signals from all their five senses
- Sometime around the 34th week they take the pre-birth heads-down, bottom-up position. If they’re in the breech position your doctor will probably turn them around at week 37
What should I worry about during the third trimester?
If you have any of these symptoms, get medical help:
- Heavy vaginal bleeding
- Severe vaginal pain
- Severe pain in the lower abdomen
- A high fever over 101.5 Fahrenheit
- Sudden mysterious weight gain
Things to avoid in the third trimester
It makes sense not to venture too far from home during the third trimester. Here are some other things to be wary of.
- Avoid lying on your back, which forces the baby and bump down so it compresses the vein carrying blood to your heart
- Steer clear of hot tubs and saunas to avoid getting too hot
- Make your baths a maximum of 37C
- Don’t exercise in hot weather
- Avoid alcohol completely
- Don’t eat raw or undercooked foods, which can contain infectious bacteria
- Don’t drink unpasteurised milk or juice
- Avoid soft cheeses like Brie and feta unless they’re pasteurised
What are the signs labour is going to happen?
- By around the 36th week you start to waddle as your baby drops into position
- Bloody show is a mucus tinged pink or brown with blood, a sign labour is underway
- You’ll feel pelvic pressure and cramps in the groin as the cervix starts to dilate
- Your waters can break at this time, but might not break until later
- You’ll get Braxton Hicks contractions, which tend to ease as you move around
- You’ll eventually get labour contractions, which get worse the more you move
What are the signs of labour?
Backaches are very common pre-labour thanks to the pregnancy hormone Relaxin, which loosens the joints ready for the birth. Backache also happens when your growing bump pulls your centre of gravity forward. It helps to put your feet up. You might also feel a very sharp pain in your back down your legs, which could be sciatica.
Varicose veins in the lower body are common simply because of all the extra blood you’re pumping around. These should disappear once you’ve given birth. Stretch marks are mostly down to your genes – simply moisturise and hope for the best.
Prelabour diarrhoea can turn up when the muscles in your rectum and elsewhere loosen in preparation for the birth. And the large ligaments that support your abdomen can start to ache as they struggle to hold up your bump. You might feel cramps or sharp pains. There’s nothing you can do about it except relax.
Your body and your baby are working hard in the background, and all that hard work leaves you feeling very tired. Eat well and often, stay active, and get as much sleep as you can. When your uterus pushes your stomach upwards you might end up with acid reflux.
Lightning crotch is quite dramatic, as you can tell by the name! No one knows for sure what causes it but it feels like a sharp shock to the crotch area. Some say it’s the baby pressing on a nerve. Whatever the cause, it helps to change positions and it should only last for seconds.
Cramped legs, peeing every five minutes and general aches are the norm in the third trimester, which often means insomnia. If it becomes too much to handle, talk to your doctor. When you sleep, you might get all sorts of strange dreams. And because you’re off-balance thanks to your belly you might find you’re a lot clumsier than usual.
Bladder control can become tricky with the extra weight on your pelvic floor. Your boobs will grow like mad. You can easily put on 8 to 10 pounds in the third trimester, but you can just as easily shed a few pounds at the end of month nine.
Things to do during the third trimester
Here are some essentials to add to your third trimester checklist.
- Count your baby’s kicks from week 28 and watch out for changes in month 9
- Watch the weight gain. If you haven’t put enough on or have gained too much, your doctor can help you get back on track
- Keep exercising right up to your due date
- Have all the relevant third trimester checkups: glucose screening by week 28 or early in month 7. An anaemia test at about month 7, a group B strep test in month 9, and your month 9 cervical examination
- Familiarise yourself with the hospital
- Pick a paediatrician
- Buy baby clothing and equipment
- Enjoy your childbirth classes and learn all you can
- Prepare either for breastfeeding or bottle feeding
- Know what to expect from labour – including how you want to manage the pain
- Make a birth plan
- Set up the nursery
- Do a big supermarket shop so you’re well stocked at home
- Pack your hospital bag
- Learn what to expect after the birth
Now you know what to expert in the third trimester. Have you thought about collecting cord blood?
Will you collect your baby’s cord blood?
It makes sense to consider collecting your baby’s cord blood immediately after the birth, to store for the future. It could save their life one day. Make the decision in good time and have your collection kit ready in your hospital bag. You can find out all about umbilical cord blood collection here.
This article does not provide medical advice and is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the Biovault Family website.