Your baby is the size of a sweet potato

18 Weeks Pregnant: Your Baby’s Development

When you are 18 weeks pregnant, your little one is developing a unique characteristic: fingerprints. That’s not all, the foetus is growing fingernails and toenails. Reflexes are also developing this week and the foetus already has a strong grip.

When it comes to facial features, eyebrows and eyelashes have started to appear, and the eyes can move − though the eyelids are still fused shut. The mouth can also open and close.

Play your favourite music nice and loud! Why? Around this time the foetus may start to respond to loud noises, and even move around in response − though you may not feel it yet.


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The Size of the Foetus at 18 Weeks Pregnant

When you’re 18 weeks pregnant, the foetus is around the size of a sweet potato, measuring about 14 centimetres from crown to rump and weighing around 190 grams.

The illustration below shows how things may be looking inside your belly this week:

Baby at 18 weeks pregnant

Mum's Body at 18 Weeks Pregnant

Have you felt any movements yet? Typically, you'll feel this fluttering for the first time sometime between 16 and 24 weeks of pregnancy, but if this your first pregnancy it's more likely to happen after 20 weeks.

If you've felt this swirling, rolling feeling already – how exciting! If you haven't felt any movement at 18 weeks pregnant, don't worry. Every pregnancy is unique and you may just need to be patient. Soon enough, you'll feel all kinds of kicks and prods. Of course, speak to your doctor or midwife if you're at all concerned.

For when you do feel your little one move, don’t forget to download our pregnancy guide because it includes a handy foetal movement tracker.

18 Weeks Pregnant: Your Symptoms

Here are some of the symptoms you may be experiencing at 18 weeks pregnant:

  • Dizzy spells. Low blood pressure can leave you feeling woozy, particularly if you get up quickly. Take things nice and easy.

  • Leg cramps. Around 18 weeks pregnant leg cramps may start to strike. Stretch your calf muscles occasionally and stay well hydrated.

  • Nosebleeds or congestion. Thanks to a surge in hormones and increased blood volume during pregnancy, mucous membranes in the nose can swell up. This means you might experience nosebleeds and nasal congestion. You can reduce congestion by rinsing your nose with a salt water solution.

  • Swollen feet. You may notice your feet swelling due to water retention, a condition known as oedema. This normally occurs from the second trimester onward. Relieve the swelling by raising your feet throughout the day, exercising, and drinking lots of water. If you notice sudden swelling, contact your doctor, as this can be a sign of the blood pressure disorder called preeclampsia.

  • Dark line on the abdomen. You might see a dark line starting to appear down the middle of your growing belly. This is called the linea nigra and is completely normal. It will likely disappear within a few months of you giving birth.

  • Hair changes. Your hair may appear thicker and shinier.

18 Weeks Pregnant: Things to Consider

  • During pregnancy you don’t actually need to eat for two. In fact, until you are six months pregnant you won’t really need any extra calories at all. Talk to your midwife for tailored advice and check out our article on pregnancy weight gain. Typically, mums-to-be gain about 10 to 12.5 kilograms during pregnancy but most of this is gained after 20 weeks.

  • You might have more energy this trimester, so this could be a good time to consider going on a holiday. Before picking a destination, read up on flying while pregnant and ask your midwife for their advice, too. If you get the green light, it could be time to pack your bags and enjoy a few days of rest and relaxation.

  • You may notice that everyone from close relatives to complete strangers feels compelled to offer advice about your pregnancy. Although unsolicited opinions can be annoying, try to take them in your stride. You don't have to explain yourself to anyone. A simple ‘Thanks, I'll keep that in mind’ should do the trick. Try to remember that people mean well and they're excited for you. You may even find some of the parenting tips you get are actually helpful.

  • You might want to have a birth plan for labour and childbirth. Look into it and discuss the idea with your midwife. If it’s something you feel would be beneficial for you, start thinking about what preferences you might like to include in your plan. The most important thing to keep in mind while writing your birth plan is that during labour and childbirth things don’t always go to plan!

  • You might have heard of hypnobirthing and be wondering if this form of childbirth class could be a good fit for you. Experts say the ideal time to book a course is after your mid-pregnancy ultrasound scan, so now is a great time to start researching a hypnobirthing course in your area if this is something you would like to do. Your doctor or midwife will be able to help you find a course in your area, and you might like to ask other moms in your network for their tips as well.

18 Weeks Pregnant: Ask Your Doctor

  • Will you be having a mid-pregnancy ultrasound exam, and when will it be scheduled?

  • When can you find out if you’re having a boy or girl?

  • Can you continue with the exercise you already do or is it time to make changes?

  • Can you get free prescriptions and dentist visits?

  • What should you think about including in your birth plan?

18 Weeks Pregnant: Your Checklist

  • If your growing belly is straining out of out of your normal clothes, it may be time to look at some maternity wear. Don’t feel you have to go on a spending spree as these clothes may only be suitable for a few months. Supermarkets and charity shops have affordable options, or you could ask friends with young children if they have anything to spare.

  • Think about telling your work about your pregnancy, if you haven’t already. Before you do, read up on your maternity leave rights and responsibilities.

  • Take our Baby Arrival quiz to discover just how prepared you already are.

  • Struggling to find the perfect name? Check out our Baby Name Generator to help you find the right one.

  • Sign up for even more weekly pregnancy tips:

How we wrote this article
The information in this article is based on the expert advice found in trusted medical and government sources, such as the National Health Service (NHS). The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.