18 weeks pregnant

How big is my baby at 18 weeks pregnant?

By week 18 your baby will be about 14.2cm long, weighing nearly 190g and similar to a large onion in size.

Their nerves will now be forming a protective covering of myelin which is vital for their nervous system to develop and function properly after birth.

Your baby is using your tummy as quite a little activity gym by week 18 and doing a whole lot of kicking, rolling and tumbling around. Now that they have developed a grip, they will be grasping hold of their umbilical cord too – a built-in play thing! If you are having a little girl, she will already be developing eggs in her ovaries at 18 weeks – how amazing is that? Your baby's genitals will now be formed and in place, and if you’re having a boy they might be visible during your week 20 anomaly scan, although it might not be possible depending on your baby’s positioning.  

Did you know?

• At 18 weeks your baby will be about 14.2cm long, weighing nearly 190g and similar to an onion in size
• Your 18-week foetus is working his or her muscles and practicing all kinds of moves from hiccuping to kicking

You at 18 weeks pregnant

The sonographer will be making sure your baby's organs are all as they should be, and that your placenta is healthy and in the right place. While they are carrying out these checks, they might have the monitor turned away from you, but you will be able to see your baby once they have finished.

If you do not want to know what you are having, make sure you tell the sonographer, so they do not inadvertently let any important information slip!

It can sometimes be hard to decipher ultrasound images, so don't feel bad if you can't quite work out what part of your baby is what – just ask the sonographer to point it all out to you. And of course, don't forget to get the latest pic of baby for your album!

Pregnancy hormones do some weird and wonderful things to your body, but it’s not just your physical health that’s affected. Hormones can also unsettle your mental health from time to time, so looking after your emotional wellbeing in pregnancy is equally important.  

It’s perfectly normal if you’ve found yourself worrying about any of these questions and concerns that mums-to-be often have:

• I’m scared about giving birth
• Will my baby be healthy?
• Will I be a good mum?
• Could previous pregnancy problems happen again?
• Have I eaten/drank anything that could harm my baby?
• Will my partner and I still have a strong relationship of our own?

Likewise, it’s not uncommon for the physical effects of pregnancy to get you down. Sound familiar?

• I feel sick all the time
• I’m so tired I can’t get anything done
• I feel I’m losing control of my body
• I feel bloated and fat
• Will my body ever be the same again?

It’s normal to worry and stress about these things, but if these feelings won’t go away, it can be a sign of something more serious. 

If you feel your pregnancy worries are starting to get you down and making you feel anxious, make sure you talk to someone. If you don’t feel your partner will understand, talk to family and friends you can trust and identify with, and who may also have young children. 

Your midwife will also be able to offer you support to help manage your feelings so don’t be afraid to discuss your worries. They are just as concerned about your emotional well-being as your physical health and they won’t judge you for having these feelings.

Did you know?

• About one in four mothers give birth by Caesarean section each year almost triple the number of women that were having them 10 years ago
• Tell the sonographer if you want to find out your baby's sex at the 20-week scan - be prepared, sometimes it's not possible to see
• About 30% of pregnant women snore because of increased swelling in their nasal passages
• If you crave fatty snacks try increasing your calcium intake
• Almost three-quarters of mums produce more milk in one breast over the other
• Placenta is Latin for "cake"

What to think about in week 18 of pregnancy

How tempting are all the little baby clothes in the shops and catalogues? Very! If you are starting to build up a collection already, think about planning ahead too, and not just buying newborn items, particularly if you spot bargains in the sales (but think of what season you will be in when your baby reaches that size! Sleeveless rompers in November? Brrr!)  

Bear in mind too, that you will no doubt end up with a ton of tiny baby clothes as gifts once your little one arrives. So our top tip? Stock up on the next sizes up so your bubba will be well stocked with gorgeous garments for a good few months after their arrival.

You may have already thought baby names at this stage, or it may be starting to send your head in a spin. Even though you won’t know yet whether you should be edging towards pink or blue, you might like to get some top names in your mind for both eventualities. 

Perhaps you're looking for something a little less traditional and a little more cool, yet you may not feel you want to go too ‘out there’ with a name that may not create too much of a fuss.

When you’re heading towards the halfway point in your pregnancy you may find yourself suffering with niggles and aches that you accept as a pregnancy symptom, but if you don’t feel great and it lingers, always have a chat with your midwife as a starting point for some reassurance.

Don’t forget that your body is busy working a total miracle during pregnancy – quietly going about its daily business while also growing and protecting a brand new baby. So it’s no wonder you’ll feel and notice plenty of changes from here on in. Most pregnancies go smoothly and niggles and symptoms pass without too much notice, but of course some symptoms can be a sign of something more serious.

Signs and symptoms at 18 weeks pregnant

Baby movements (referred to as fetal movement)

Although every pregnancy is different, from around now, you will start to feel your baby move. Timings can be different for every mum-to-be so if you haven’t felt anything yet, don’t panic. In the early days your baby’s kicks don’t feel like kicks as such, many describe them as feeling like bubbles initially and they get stronger as time goes on, forming into kicks, punches, swooshes, flips and turns in time. Your unborn baby moving is an important sign that all is well. There are no set numbers of movements a woman should feel, but it is important that you learn to recognise your baby's normal pattern of movements so you know what feels normal for your baby. Find out more about Tommy’s #movementsmatter information and how you can get to know your own baby’s pattern of movements.

Swollen feet and ankles

In simple terms, it is swelling in your body, usually your ankles and feet. Oedema is caused because your body is holding on to more fluid than usual common in lower legs, ankles, feet it can also occur in your face, hands and arms. If you are suffering with swelling, try resting with your legs higher than your hips and increasing your exercise to boost circulation (as well as resting and putting your feet up when you can). Avoid standing for a long time, wear comfortable shoes and socks, stay hydrated and active. If you are suffering badly, there is the option to wear special maternity support tights that can also help to reduce swelling.

Watch our videos below on:

Video 1: What can my baby understand and feel in the womb? (NHS content)

Video 2: Pregnancy exercise with Nuffield Health