Pregnancy Week by Week

18 Weeks Pregnant

22 Weeks to Go!

5.6

inches

6.7

ounces

Baby is as big as an artichoke

By The Bump Editors

Updated May 31, 2024

Medically Reviewed by Patricia Pollio, MD

Fact Checked by Elizabeth Bryson

In this article:

Key takeaways at week 18 Video highlights at 18 weeks 3D anatomy views Baby's development at week 18 Pregnancy symptoms this week Your body at 18 weeks Tips for week 18 Frequently asked questions Checklist for week 18

Key Takeaways at 18 Weeks Pregnant

Quickening—that’s the term for those early fluttery movements you feel. If you haven’t felt a little jab yet, just you wait.
Baby is doing all sorts of tricks in utero—swallowing, hiccuping and flipping!
Symptoms will come and go. You might be experiencing round ligament pain, swelling and varicose veins (oh joy!). Meanwhile, that bump of yours is probably no longer in stealth mode.
That all-important 20-week ultrasound (a.k.a. anatomy scan) should be on your schedule for the next week or so! Get ready to see baby on screen.

Starting around 18 weeks pregnant, you should begin to sleep on your side instead of your back. That’s because baby (and your uterus) is getting big enough to press against large veins in the back of your abdomen, which can reduce the amount of blood going to your heart, making you feel lightheaded—or worse, lowering your blood pressure. Sounds scary, but it’s totally preventable by simply sleeping on your side. Of course, your veins aren’t the only things that are prone to pressure—you are, too! At pregnancy week 18, there’s a lot going on. Be sure that you plan some time to take breaks and unwind.

Video Highlights at 18 Weeks

Watch Week 18 Highlights

3D Views: My Baby, My Body

See their progress for yourself with our 3D interactive tool.

Baby at Week 18

What the heck is baby doing inside your 18 weeks pregnant belly? A lot! Your 18-week fetus is working their muscles and practicing all kinds of movements. Can you believe baby is yawning, hiccupping, sucking and swallowing? They’re twisting, rolling, punching and kicking too—and they’re are big enough that you might be able to feel them doing it!

For the past few weeks, baby’s hearing has been developing, and at 18 weeks, the pieces are in place for them to begin hearing sounds inside your womb (like your heartbeat). The ears, which have been slowly moving to the sides of their head, are finally set in place and sticking out; meanwhile, more sophisticated nerve and bone development is occurring in the middle and inner ear canals.

Are you having a boy or a girl? Soon, you might be able to tell on an ultrasound: Baby’s external genitalia are fully formed and visible, allowing you to see either a penis or clitoris (though there’s no guarantee you will, since sometimes babies don’t cooperate for ultrasounds!). If you’re having a girl, the major organs of her reproductive system—the fallopian tubes and uterus—are also in place.

How big is baby at 18 weeks?

At 18 weeks pregnant, baby is about as big as an artichoke. Baby's about 6 inches long and about 5.5 ounces now and keeps growing quickly. That's why you’re probably feeling so hungry!

What does baby look like at 18 weeks in the womb?

Baby’s face and head are taking shape. The facial features and ears are moving into place—but you need to wait a while to see if they have your eyes or your partner’s nose! Also, an 18-week fetus now has a working digestive system, as well as a light coating of hair all over their body that’s called lanugo.

18 weeks pregnant is how many months?

At 18 weeks, you’re about four months pregnant. Since pregnancy is 40 weeks long, at 18 weeks pregnant you’re nearly half-way there!

18 week ultrasound

At 18 weeks pregnant, the big ultrasound is on your calendar for sometime in the next few weeks. The mid-pregnancy ultrasound (a.k.a. anatomy scan or level-two ultrasound) is a detailed examination of baby’s entire body. It’s a pretty cool peek inside! Your 18-week fetus will be measured to make sure their growth is on track. Major organs will be checked for proper development. And amniotic fluid, placenta location and fetal heart rate will all be examined as well, to be sure baby is thriving.

If you’re 18 weeks pregnant with twins, there’s a membrane that separates your two 18-week fetuses. As they wiggle around in there, they’ll push fluid around and the membrane will shift slightly—you’d probably be able to see that on an 18 weeks pregnant ultrasound. Yes, if you’re 18-weeks pregnant with twins (or other multiples), both (or all) babies’ anatomy will be scanned at one appointment.

If you want to know whether you’re having a boy or girl, the technician will be able to tell you with 95 to 100 percent certainty at the mid-pregnancy ultrasound—as long as baby moves into a position where their organs are visible. Some babies don’t exactly cooperate!

Pregnancy Symptoms at Week 18

Not only are you super busy preparing for baby, but you might be having some not-so-fun 18 weeks pregnant symptoms, like swollen feet or hands, backaches, leg cramps and nosebleeds. And the stress and discomfort can keep you up at night around week 18 of pregnancy. Here’s the scoop on the 18 weeks pregnant symptoms you may be feeling:

Swollen feet and/or hands

Swelling can be an annoying pregnancy symptom. It’s nothing to worry about as long as the swelling isn't sudden or severe. If it is, tell your doctor right away.

Backaches

Baby is putting a lot of pressure on your insides, causing aches and pains in your back. Plus, pregnancy can take a toll on your posture, which can also lead to backaches.

Leg cramps

Cramps can be a sign of dehydration, so drink up!

Varicose veins

These visible purple or blue veins are swollen due to all that extra pressure on your circulatory system. To deal with them, change positions often, prop your legs up when you can, get plenty of exercise and avoid tight clothes and shoes.

Trouble sleeping

Your mind is working overtime and you're getting more and more uncomfortable. This can wreak havoc on your ability to catch the ZZZs you need.

Nosebleeds

Bet you never expected these! Increased pressure on the veins in your nose may be making it bleed more than usual. If you have a nosebleed, apply pressure by pinching your nose for 10 to 15 minutes. An ice pack can also help stop the bleeding.

Baby kicks

Whether you’re 18 weeks pregnant with twins, triplets or a single baby, you’re probably feeling not just tiny flutters but more definitive sensations resembling actual kicks. They’re getting stronger!

What should I be feeling at 18 weeks of pregnancy?

If you’re tired and achy, you’re not alone—week 18 symptoms can really wear you down! That’s why it’s important to take care of yourself by eating well, exercising and getting plenty of water and sleep. If you aren’t experiencing the common symptoms, take advantage of the energy you have to start planning for baby’s arrival. Another thing on your to-do list: shopping for maternity clothes. Your 18 week baby bump may be showing!

Your Pregnant Belly at 18 Weeks

Your 18 weeks pregnant belly is rapidly expanding—all the stretching and pressure it’s causing are what’s prompting those symptoms.

Weight gain at 18 weeks pregnant is recommended to be about 1 to 2 pounds per week for women of normal BMI, whether you’re having one baby or you’re 18 weeks pregnant with twins. Let your doctor know if you have any concerns with your weight gain so far. Drastic or sudden weight gain or weight loss could be signs of a problem.

If you’re 18 weeks pregnant and not showing much, everything is probably a-okay. Remember: Every pregnant body is different, and your uterus will grow up and out of your pelvis at a slightly different time than another pregnant woman’s does.

What happens at 18 weeks of pregnancy?

You’re busy taking care of yourself to help baby grow! You still have a couple of weeks until you reach the midpoint of your pregnancy, when you’ll likely have your next big doctor appointment. You can also look forward to an ultrasound, where you get to check in on your little one.

Tips for 18 Weeks Pregnant

Here’s what you can do this week to prioritize your health and wellness—and that of your little one too!

Get a leg up on cramps

In addition to drinking plenty of water, you can help prevent leg cramps by including the right nutrients in your diet. Make sure you’re getting calcium, magnesium and potassium, either in your prenatal vitamin or in fresh fruits and vegetables.

Treat your feet

Your feet may be swollen thanks to all that extra fluid you’re carrying in your body to support baby at 18 weeks, and gravity isn’t helping matters. You can find some relief by using pillows to elevate your feet above heart level—another good reason to relax and get some rest when you can! If swelling is especially bad, or you’re on your feet a lot, try compression socks.

Stretch it out

Show your aching back some TLC with a couple of simple yoga-style stretches that ease pain. Start in tabletop position on your hands and knees with a flat back, and then round your back upwards as you gently pull your stomach up in cat pose. Hold it for a few seconds before resuming tabletop. Child’s pose is also great—and it’s super relaxing too!

Buy a body pillow

If you’re craving a good night’s sleep (and really, who isn’t?), try using a pregnancy pillow. It can help you maintain a comfortable sleeping position on your side to accommodate your 18 weeks pregnant belly, and it can even reduce back and hip pain too.

Frequently Asked Questions

Do varicose veins go away after pregnancy?

For the most part, varicose veins formed during pregnancy will go away after a few months, though some may also stick around. Addressing your varicose veins during pregnancy with pregnancy-safe treatments, like keeping legs elevated, wearing supportive garments, staying hydrated and staying active can keep varicose veins from getting worse and make them more likely to go away after pregnancy. After about four months postpartum, if your veins aren’t improving and you have concerns, talk to your provider about further treatment.

What are the best pregnancy sleeping positions at this point?

In general, the best pregnancy sleep position is on your left side. However, what’s most important is to avoid sleeping on your back around this almost-halfway point of pregnancy, so as not to compress the vena cava, a large vein that carries blood to your heart and baby.

What does round ligament pain feel like in pregnancy?

Feeling pain in your lower abdomen, hips or groin? It could be round ligament pain, caused by stretching of the muscles that support your uterus. You might feel round ligament pain on both sides of your pelvic region or only one. It may be dull, but honestly, it’s often pretty noticeable as a sharp, throbbing or shooting pain triggered by sudden movements or changes in position.

Although it can be hard to tell the difference between round ligament pain and cramps or even a more serious pregnancy issue, round ligament pain typically gets better with rest and shouldn’t be accompanied by other symptoms like fever, nausea or vomiting, or vaginal bleeding.

Can babies hear in the womb?

At 18 weeks, baby will be able to begin hearing sounds within your own body, like your heartbeat, digestion and blood flow. These noises are just the beginning though! Baby will be able to hear noises coming from outside the womb closer to 27 weeks, at which point their hearing abilities will only keep getting better. By the time baby is full-term, their hearing will be as good as an adult’s, and they’ll become familiar with the sound of your voice, any music you regularly play and any other sounds that recur during your daily activities.

When should I stop traveling during pregnancy?

Travel during pregnancy is generally safe, and depending on the mode of transportation, many women receive the green light to travel pretty close to the end of pregnancy.

For women with uncomplicated pregnancies, the usual recommendation is to stop domestic air travel by 36 weeks, though your provider and airline may provide different restrictions. The cutoff is also likely to be earlier for international travel, which brings additional concerns about access to healthcare, potential diseases and illnesses and insurance coverage for travel emergencies.

Travel by car is generally less risky, but it’s important to talk to your provider about ways to prevent worsening of common pregnancy symptoms like back pain, nausea and leg cramps during periods of extended car travel.

I have always been lean, and I didn't look noticeably pregnant until my last few months. Most people get jealous over things we have no control over. I really loved my body the most during this time. I felt like I was glowing, and smiling the whole time. I loved having a buddy with me all the time. I was never alone. I can't wait to be pregnant again and rock my belly in the summer! -Kayla B., mom of one -UGC

Pregnancy Checklist at Week 18

Reminders for the week:

Read up on what happens at the mid-pregnancy ultrasound

Research breast pumps (some are covered through your insurance)

Take advantage of this "honeymoon stage," plan a date night and enjoy some intimacy with your partner

Please note: The Bump and the materials and information it contains are not intended to, and do not constitute, medical or other health advice or diagnosis and should not be used as such. You should always consult with a qualified physician or health professional about your specific circumstances.

Sources

Cleveland Clinic, Quickening in Pregnancy, April 2022

American Pregnancy Association, First Fetal Movement: Quickening

American Journal of Roentgenology, Assessment of Fetal Swallowing with Gray-Scale and Color Doppler Sonography, November 2005

Mayo Clinic, Pregnancy Week by Week: Fetal Development: The 2nd Trimester, June 2022

Cleveland Clinic, Round Ligament Pain, July 2021

American Pregnancy Association, Swelling During Pregnancy

Cleveland Clinic, Varicose Veins While Pregnant, May 2022

Johns Hopkins Medicine, The Second Trimester

Cleveland Clinic, 20-Week Ultrasound (Anatomy Scan), April 2022

Sleep Foundation, Pregnancy Sleep Positions, November 2022

Sleep Foundation, Sleeping While Pregnant: Second Trimester, March 2023