18 weeks pregnant: Baby’s development, symptoms and top tips

At 18 weeks, your baby is about the size of a sweet pepper – around 14cm long.

Your baby is so busy, kicking, wriggling, and moving their arms. Their hearing continues to develop, so every time you talk, they are growing more familiar with the sound of your voice. If you feel silly talking to your bump, you can always talk to your partner about your hopes and dreams for your little one – it will have the same soothing, bonding effect.

Those swallowing reflexes are still developing, and the baby will be putting them to use, sucking up amniotic fluid.

If you had a 4D scan of your baby this week, you might capture them yawning – something that’s thought to relate to the development of their central nervous system, rather than because they’re tired or bored. Either way, it’s mega cute!

Soon your baby will begin to form myelin, the whiteish mix of fat and protein that protect nerve cells in the nervous system and helps messages travel along the nerve pathways faster.

In week 18, you might feel those nesting instincts kicking in. You’ll want to create a safe and comfortable home for your future family, and your creative juices will be flowing. Even though you’re making all these plans, don’t overdo it – there’s still plenty of time before the baby comes.

Taking care of your changing body

Something else you might have noticed is that your centre of gravity has shifted as your bump has grown. Practice keeping your balance by alternating between putting your weight on one foot and then on the other when you’re standing up.

You may also start to feel some back pain, particularly in your lower back, as your bump gets heavier and your centre of gravity changes.

It's a good idea to be extra-careful if you need to lift any heavy objects – or better yet, ask someone else to do it for you. A soothing back massage from your partner can help with mild aches and pains, but see your doctor or GP if any pain becomes severe or intense.

If you’re concerned that you’re gaining too much weight, check our weight chart for a guide.

Stay active

Swimming and walking are both excellent ways to help your body stay strong enough to handle the extra load you're under - and it's a good idea to start doing some pelvic floor exercises as well, if you aren't doing them already. One thing you can do to avoid spider veins (varicose veins) and help your legs is take sufficient breaks and sit or lie down with your legs in a raised position.

Tips on exercising when pregnant.

18 weeks pregnant – bump is popping

As you excitedly watch your growing baby bump, you’ll notice that your body is beginning to feel different. Walking will become more of an effort, your legs will feel heavier and you’ll need more breaks than before – this is completely normal.

You might also find it harder to get to sleep if you normally sleep on your back, because your belly will be pressing down on your organs and blood vessels. A breastfeeding pillow (if you’ve already got one) can help you sleep comfortably on your side if you put it between your legs.

Up your iron intake

It's completely normal to feel tired more often (there’s a lot going on inside you, after all), as during pregnancy you need lots of trace minerals which you might not always get. Therefore, we recommend that you increase your iron intake, as iron binds the oxygen in your blood and helps both you and your baby get the oxygen you need. Focus on eating meals and drinking juices that contain high amounts of iron, such as a mild juice with red fruits.

Be proud of your bump!

Some of the great advantages of being pregnant include thick glossy hair, that lovely glow and an amplified cleavage. Don’t be surprised if your partner thinks you're extra-gorgeous right now - many do!

You might also find that total strangers want to talk to you about pregnancy or babies - lots of people just love pregnant women! This doesn't mean, of course, that you have to put up with intrusive comments, but if you're keen to chat about your pregnancy, you'll almost certainly find lots of people to do it with!

Sudden movements and unreliable blood pressure

You might find as your bump grows that your body doesn’t respond as well to sudden movements. As your uterus grows, it starts to exert pressure on the surrounding organs and blood vessels. This means that if you’ve been lying down or sitting for some time, you probably don't want to get up too quickly in case you become dizzy.

Your blood pressure is currently a bit lower than normal and may drop rapidly for a few moments if you’re doing something strenuous, which can make you feel faint. If this happens, sit or lie down with your legs in a raised position. It won’t take long for your body to adjust, and you’ll soon feel better.

Your body is working hard and is transporting more blood around your body through your blood vessels. Your doctor or midwife can test regularly to see if your blood pressure is consistently too low. In almost all cases, low blood pressure can be resolved with conservative therapy to suit the rhythms of everyday life during your pregnancy. Vein training, which involves tensing and relaxing your leg muscles, can also help with low blood pressure and varicose veins.

Dealing with aches and pains

There are also other sudden movements your body doesn’t cope so well with – coughs, sneezes, and rolling over in bed can all cause you to clutch your bump to alleviate sudden, sharp pains that occur in your round ligaments. These are the ligaments – one on the right side, one on the left – that join your uterus to your pelvis, and they’re under pressure as your bump grows.

You’ve probably heard of the hormone relaxin, which enables your joints and ligaments to flex and stretch so that your body can accommodate both pregnancy and birth. Unfortunately, a side effect of this is that all your joints become more vulnerable to strain.

You can take paracetamol for pain where needed, but your best measure against these types of aches and pains is to not overdo it. Continue with gentle stretches, exercise, and support your bump with your hands when you make sudden movements.

Supplements to avoid

During pregnancy you should avoid supplements containing vitamin A, as too much vitamin A can be harmful to your baby’s development. Liver and liver products (including cod liver oil) are high in vitamin A and should be avoided.

Possible questions for midwife or doctor

Your next antenatal appointment is likely to be the 20-week scan, so here’s the big question: do you want to know the baby’s sex? We’ve made a list of pros and cons to finding out the baby’s sex to give you something to think about as you make your decision. Remember, it is up to you and your partner whether you find out the sex of your baby. There’s no right or wrong way to approach it.

Your next ultrasound will be in the next few weeks. This is called the anomaly scan, or the 20-week scan, and is a great opportunity to see how your baby’s progressing. Whereas you may have struggled to recognise your baby in the 12-week ultrasound scan picture, at almost 20 weeks your baby is recognisably baby-shaped. Get a picture for their baby book if you can – this one will be much clearer than the last one!

What should I be feeling at 18 weeks pregnant?

At 18 weeks you are probably eagerly anticipating feeling those first baby movements. Don’t panic if you haven’t felt them move. It’s normal for first-time mums to take longer to feel baby movements, and the NHS advises that first movements will probably be felt between 16 and 24 weeks.

Hopefully, you’re feeling energised and upbeat about your pregnancy at this stage, despite the niggling aches and pains. If you’re feeling low or anxious, don’t suffer in silence. It’s very normal to feel nervous about the birth, and about parenthood. If you feel like this anxiety is crowding out all other thoughts, though, tell your midwife. They’ll be able to guide you to the support you need.

Where is baby located at 18 weeks?

Your uterus is now encroaching on your other organs and taking up space beyond your pelvic cavity. If you were to see your midwife this week, they would be able to feel the top of your uterus in your lower abdomen.

How many months is 18 weeks pregnant?

You are just over 4 months pregnant at 18 weeks. You will be 5 months pregnant at around 21 weeks.

Are cramps normal at 18 weeks pregnant?

For most people, pain in the abdomen at this stage can usually be explained away by round ligament pain or trapped wind. Some people will get Braxton Hicks this early in their pregnancy, but this isn’t usually painful. If you’re experiencing painful abdominal cramps, or bleeding, call your midwife.

Can my baby feel me touch my belly at 18 weeks?

There is some evidence to suggest that babies respond to touch from as early as 21 weeks. So, while that’s a few weeks off yet, it’s possible that your baby is aware of you touching your belly at 18 weeks. There’s no harm in assuming they can, and racking up plenty of comforting belly rubs for you both.

Got questions? At the HiPPBabyClub, we bring you real-world advice and support from HiPP parents, midwives, nutritionists and more. Join our Baby Club to find out more.