31 weeks pregnant

You and your baby's development

What's happening in week 31 of your pregnancy

Week thirty one and your baby is just weeks away from being in your arms!

At a glance

  • Your baby can now tell when it is light or dark
  • You may get Braxton Hicks around now
  • If you have other children, prepare them for baby's arrival
31 Weeks pregnant

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How big is my baby at 31 weeks?

At week 31 the average baby will be around 41.1cm long, likely weighing just over 3lbs and although they will not get much longer at this stage, but they will continue to put on weight each week.

Their arms, legs and body are now in proportion with their head and their organs are continuing to develop including the bladder which will now be passing water through it. Their bone marrow is now doing the all important job of producing red blood cells, up until this point their liver had performed this job.

They will also know when it is light and dark now, but still won't necessarily keep to a day or night time sleeping or moving about regime! 

But with only a few weeks to go you have definitely started to notice your baby has now settled in to a regular pattern of movement.

You should be able to recognise what is 'normal' for your baby now. If you notice any change to this, then do call your midwife straight away.

Facts to know about your baby in week 31

  • At week 31 the average baby will be around 41.1cm long, likely weighing close to 3lbs
  • Your baby's finger nails are fully developed and may need cutting when they're born

You at 31 weeks pregnant

You might be getting Braxton Hicks contractions now, and be feeling regular tightening in your tummy.

Braxton Hicks are sometimes called practice contractions, but they should not be painful. 

You might also be feeling more tired now as your due date is well and truly in sight, so it is important to get as much rest as and when you can, particularly if you are having trouble sleeping at night. Advice from Tommy's says that in the third trimester it's safest to sleep on your side, as research has shown that sleeping on your back is linked to an increased risk of stillbirth, which includes daytime napping as well as night time sleeping.

You might be experiencing more heartburn now, too, as your growing baby puts extra pressure on your tummy - your midwife might suggest an antacid if you are finding it too uncomfortable.

In fact, you might find your whole digestion system is a bit out of kilter in late pregnancy - again, speak to your midwife if your symptoms are bothering you. Some, like constipation and wind can be easily remedied through diet.

What you eat during pregnancy can affect your amniotic fluid with particular smells and flavours. By week 31 of your pregnancy your baby's brain and tastebuds have matured allowing them to taste flavours in the fluid they consume. Research has also suggested that the food you eat in pregnancy will shape your baby's food preferences when they start to eat solid foods.

Facts to know about you  in week 31

  • Wrinkles can actually disappear. Hormones can also plump out your skin, making wrinkles disappear
  • Your baby's eyes can now tell when it is light or dark
  • The timing of when your baby's head engages does not indicate when you'll go into labour
  • You may get Braxton Hicks around now. They are practice contractions of the uterus
  • Feeling hot? The temperature of amniotic fluid is a higher temperature than the rest of your body

What to think about in week 31

If you have other children, they are no doubt on the countdown now for the arrival of their new brother or sister, and will have been well prepped about what having a new sibling will entail – but what about other children in your family? 

If this is your first baby but you are already an aunty, your nieces and nephews might be used to having you to themselves, and potentially not having to share their grandparents with other children, either. Take some time to reassure the other little one's already in your life about what an exciting thing your new arrival is going to be for the whole family!

Now you are into your third trimester and the finish line is in sight, you may be wondering if a baby shower might be a nice way to mark your pregnancy, and also pick up a few baby essentials as an added bonus!

Until more recently a baby shower was considered something Americans and celebs do, but they have risen in popularity over the last few years and the idea has caught on big time here in the UK.

Showers are usually organised by the friends of the mum-to-be, although of course there is no reason why you can’t throw your own baby shower celebration.

By now you’re probably getting most of your big baby purchases sorted, if not, better get a wriggle on! But you may also start thinking about what other purchases may help life run as smoothly as possible once baby arrives.

If grandparents, aunts or close friends are likely to be helping you out with your little one for example, it’s a good idea to consider a spare car seat they can keep in their car so you don’t spend your life swapping car seats for car to car. 

A combination car seat could be a good option as they are designed to cover multiple groups and are most commonly used to cover 0+/1 or group 1/2/3.

Similarly highchairs are not essential straight away but it’s often a useful item that other family members might offer to buy as a gift so never too early to think about what might best suit your needs and taste.

Signs and symptoms at 31 weeks pregnant

Peeing more often

In your third trimester your bladder has more pressure from your uterus as it expands which leaves less room for your bladder to store urine. In late pregnancy the need to pee increases during the night because when you lie down some of the fluid you retained in your legs and feet during the day can head back into your bloodstream and eventually your bladder. Make sure you fully empty your bladder each time you go to the loo to prevent too many visits and urine infections.

Leaky boobs

It’s not uncommon to notice a bit of milk leaking from your nipples when you’re pregnant but this is nothing to worry about as it is simply your body’s way of getting ready for breastfeeding. It’s colostrum that is leaking at this stage.  It is the first thick, creamy milk your breasts make before producing breastmilk. If it bothers you, buy maternity breast pads to pop into your bra. Many mums find their breasts stop leaking milk in the first six to 10 weeks of breastfeeding.

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At a glance

  • Your baby can now tell when it is light or dark
  • You may get Braxton Hicks around now
  • If you have other children, prepare them for baby's arrival

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