18 weeks pregnant with multiples

Feeling some extra movement this week? It makes sense! Your babies are moving and grooving, and when they’re not, your stomach is probably growling as your appetite picks up to keep up with their growth.

Your babies are kicking and punching up a storm in the womb, and pretty soon, you’ll be able to feel more defined jabs. Week 18 is a big growth week — both for you and your babies. Let’s see what’s changing this week and what you can do to keep yourself feeling your best!

What’s new with your babies?

Those sweet little faces are becoming more defined as your babies’ facial features continue to develop. Your babies can now yawn, swallow, and hiccup. In addition to typical fetal movement, you’ll eventually be able to feel hiccups as well. 

A coating of myelin is now developing on your babies’ nerves. This is a substance that facilitates the brain’s communication with the rest of the nervous system. Because myelin is essential for your babies’ brain development, you’ll want to support this growth by consuming healthy fats, like Omega-3s and DHA.

Your babies now weigh about 6.7 ounces — about the size of an artichoke. 

How are you doing? 

Chances are, you’re feeling excited about your upcoming anatomy scan in a couple of weeks. Seeing your babies is always a thrilling experience, and this in-depth ultrasound will allow you to do so longer than ever. You’ll also have a chance to learn their sex, which can be a pivotal part of your pregnancy journey! 

Physically, you may be feeling ravenous as your appetite picks up to meet your growing babies’ needs. Fueling your body with healthy food and small, frequent meals will help you feel your best, but it’s perfectly OK to indulge from time to time as well.

Many people report experiencing dips in their blood pressure at this stage as the circulatory system expands to meet the needs of your pregnancy. This can leave you feeling dizzy, lightheaded, and weak. To combat this, avoid going from a lying or seated position to standing too quickly, and remember to drink lots of water. This period of low blood pressure generally lasts until about the midway point of the second trimester and then will gradually begin to subside. Try to take it easy, and listen to your body if it’s telling you to slow down.

Will testing take place this week?

Your anatomy scan is likely still a couple of weeks away, as most providers prefer to do this ultrasound closer to 20 weeks. If you’ve chosen to do a Multiple Marker Screen (MMS, a.k.a. Triple or Quad Screen Test), your blood will be drawn sometime between now and your ultrasound appointment. This test measures specific proteins and hormones in your blood and will give a clearer picture of your babies’ risk for neural tube defects. This test may be less helpful for a multiple pregnancy, so speak to your provider if this is an option for you.

Let’s plan ahead!

You’re nearly halfway through your pregnancy, so it’s time to start thinking about what’s available to you as an expectant parent of multiples. You may want to give your insurance company a call to see what coverage options you have, including a breast pump, if you’re planning to nurse your babies. 

If you do plan to breastfeed, it’s never too early to get support. Ask your physician for a referral to a lactation consultant who is familiar with breastfeeding multiples. Being armed with knowledge before your babies arrive will make for a much smoother process!

Reviewed by the Ovia Health Clinical Team


  • American College of Obstetricians and Gynecologists. “Multifetal gestation: Twin, triplet, and higher order multifetal pregnancies.” National Guideline Clearinghouse. U.S. Department of Health and Human Services, May 2014. Retrieved May 15 2021.
  • Mayo Clinic Staff. “Twin pregnancy: What multiples mean for mom.” Mayo Clinic. Mayo Clinic, December 13 2014. Retrieved May 15 2021. https://www.mayoclinic.org/healthy-lifestyle/pregnancy-week-by-week/in-depth/twin-pregnancy/art-20048161.
  • “FAQ: Multiple pregnancy.” American College of Obstetricians and Gynecologists. American College of Obstetricians and Gynecologists, July 2015. Retrieved May 15 2021.
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