18 Weeks Pregnancy: Signs, Symptoms & Baby Development

Hey, soon-to-be mom! Excited to enter the 18th week of your pregnancy? Congratulations, you are almost halfway through your pregnancy! Being 18 weeks pregnant is going to bring some worthwhile changes in your body. The highlight of this week is that your 18 weeks pregnant bump might feel your little one’s movement. So, let’s look at how your baby is developing along with 18 weeks pregnancy symptoms that you might experience.

18 Weeks Pregnant: Your Baby’s Development


At 18 weeks pregnant, your little one is developing a unique characteristic which are fingerprints. Pads of fat accumulating on the fingertips and toes will turn into distinguishing swirling lines.

Digestive System:

The developing digestive system has been going through its paces for several weeks already. Your baby swallows amniotic fluid, which makes its way through the stomach and intestines. That fluid will combine with dead cells and secretions in the intestines to form meconium — a black, tarry substance you'll see at the very first diaper change.


At 18 weeks, your little one’s lungs continue to develop. In this week, the smallest tubes of lungs called bronchioles begin to develop at the tips of the branches.


Around 18 weeks, your baby’s ears will begin to stand out from the sides of the head and may even begin to register sounds.

Gall Bladder:

Your baby will need bile to digest nutrients, and at 18 weeks, the gall bladder may begin to work.

Gender Parts:

If you are having a girl, her uterus and fallopian tubes will form and on the other hand, your boy’s genital parts will become more noticeable.

18 Weeks Pregnant Bump & the Size of the Fetus at 18 Weeks Pregnant

When you’re 18 weeks pregnant, the fetus is around the size of a sweet potato, measuring about 13 centimetres long from crown to rump, and weighing around 0.098 kilograms.

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

Baby Position & Baby Movement At 18 Weeks

18 Weeks Pregnant in Months

If you’re wondering, “How much is 18 weeks pregnant in months?”, the answer is you have probably now just turned five months pregnant.

18 Weeks Pregnant Symptoms for Mother: Body Changes

Baby Movements:

If this is your first pregnancy, you may feel the baby beginning to move inside your belly sometime soon. This fluttering feeling is known as quickening. As your baby gets bigger, you may notice stronger movements and maybe even kicks in the weeks to come. Because each mom is different, you may feel this movement earlier (this is common if this is not your first baby) or in some cases even later. So, even if you don’t feel any movement at 18 weeks pregnant, there is no need to worry.


At this stage of your pregnancy, your body is going through a lot of circulation changes, such as increased blood volume and rapidly expanding blood vessels, which can cause your blood pressure to drop. This can leave you feeling lightheaded if you’re not getting enough blood flow to your head and upper body.

Swollen Feet:

Being 18 weeks pregnant might make your feet grow bigger. A part of this is due to swelling caused by water retention, known as oedema, which can occur from the second trimester onwards. Hormones also play a part in growing feet. The pregnancy hormone relaxin, which relaxes your pelvic joints so your baby can fit through the birth canal, loosens the ligaments in your feet, causing the foot bones to spread. You can relieve the swelling with a footbath of cool water and by keeping your feet raised; don’t worry (and have fun!) if you need, head out for shoe shopping for a bigger size. Read more about swollen feet during pregnancy


Your heart is working 40 to 50 per cent harder than it did before you were pregnant. This effort, combined with the pressure of your growing uterus on blood vessels, can occasionally leave you feeling faint, particularly when you get up quickly. Be sure to rest frequently. Lie down on your side when you feel faint or dizzy. Low blood sugar can also lead to dizziness. Resting, lying down on your side, or eating a piece of fruit will help boost blood sugar levels and settle dizzy spells.

Baby’s Movement:

Most women first feel their little one's movements between 16 and 20 weeks. Your baby is still small, so at around 18 weeks pregnant, it'll be more of a gentle flutter than a forceful kick in your belly.

Nasal Problems:

This 18 weeks pregnant symptom is a result of high levels of hormones and increased blood volume, which causes mucous membranes to swell up, leading to nosebleeds and congestion.

Back Pain:

Along with hormonal changes, your 18 weeks pregnant bump is also growing which can lead to aches and pains in your lower back area.

Leg Cramps:

This is one of the pregnancy symptoms that strike during 18th week of pregnancy, usually at night. Try to stretch your calf muscles before bed and stay hydrated. A warm bath, hot shower, or a massage may help, too. Read more about pregnancy pains

18 Weeks Pregnant: Things to Consider

Follow a Diet Rich in Omega-3 Fatty Acids:

Getting the nutrients you and your baby need is quite important, and omega-3 fatty acids are a crucial part of a healthy diet. Omega-3s help your little one’s nervous system develop, and some research shows that they may also help boost your immune system and reduce the symptoms of depression. Look for foods that are rich in this nutrient, like salmon or other fatty fish, or get your omega-3s from vegetarian sources like flaxseed, broccoli, or walnuts.

Eat Healthy Calories:

You'll need some extra calories to support your growing baby, but you don’t actually need to eat for two. Once you reach the second trimester, this could be an extra 300 calories — half a sandwich and a glass of skim milk, say — on top of an average of 2,000 calories a day.

Parenting Advice:

You may notice that everyone, from your mother-in-law to complete strangers, feel compelled to offer advice about your pregnancy. Although unsolicited opinions can be annoying, try to take them in 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.

Mid-pregnancy Ultrasound:

In rare cases, the mid-pregnancy ultrasound reveals a problem associated with the placenta. Your doctor will tell you if he suspects either placenta accreta or placenta previa and will be able to advise you on what care you will be given to lower any risks associated with either condition.

18 Weeks Pregnant: Ask Your Doctor

Here are Things You Can Ask Your Doctor During Your Next Visit:

  • Is your baby’s level of movement and position on track for 18 weeks pregnant?

  • What are the risks and benefits of any genetic tests that may be offered this trimester?

  • Do you recommend the maternal serum alpha-fetoprotein (or MSAFP for short) screening test?

  • When will your mid-pregnancy ultrasound exam be?

18 Weeks Pregnancy: Your Checklist

  • Graciously listen to unsolicited advice, even if you’re not going to follow it.

  • Plan your maternity leave by speaking to your manager.

  • Boost your circulation by resting while lying on your side or eating a piece of fruit.

  • Make a list of foods rich in omega-3s and add them to your weekly shopping list.

  • Start collecting books to read to your baby. Get week-by-week expert tips on pregnancy to keep track of your baby’s development to ensure the well-being of both you and your baby during the entire nine months journey!

  • Start thinking about baby names for your little one. Do check out our Baby Name Generator for inspiration.

How We Wrote This Article:
The information in this article is based on the expert advice found in trusted medical and government sources. You can find a full list of sources used for this article below. The content on this page should not replace professional medical advice. Always consult medical professionals for full diagnosis and treatment.

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