31 Weeks Pregnant with Twins

Here’s what to expect when you are 31 weeks pregnant with twins:

Fetal Development

By 31 weeks in the twin pregnancy each of your twins is a little over 16″ (41 cm) long and has following measurements:

Head circumference: 11.75″ (298 mm)
Abdominal Circumference: 10.5″ (267 mm)
Femur Bone Length (about from the waist to knee): 2.3″ (58 mm)

Each baby is about the size of a coconut.

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What to Expect

Typical weight gain for Mom at this point is about one pound per week (0.6kg).

Pictures and Video

Here’s an ultrasound video of what you might see at 31 weeks pregnant with twins:

4 Critical Mistakes Expectant Twin Parents Make

Belly picture at 31 weeks:
31 Weeks Pregnant with Twins Belly

If Your Twins Were Born This Week

Your twins are early preterm and the odds of survival are better than weeks past. However, twins born during the 31st week still risk major medical complications. They could spend weeks, if not months, in the NICU. Twins born this week average a hospital stay of about 36 days.

Here are a few examples from your fellow twin parents:

(RELATED: Don't reinvent the twin parenting wheel. Get my 7 Things Every Dad of Twins Needs to Know.)

Catherine G.’s twins were born at 31 weeks and weighed 3lbs and 11 oz and 4lbs and 1 oz. They spent 5 weeks in the NICU.

Cory H. had twins born at 31 and 3 days and they spent 72 days in the NICU for mostly feedings and growing. They both had GI issues and had to use special formula and medications for acid reflux. They were 3 lb 8 oz and 4 lb 15 oz at birth.

Ben V. recounts that after being born at exactly 31 weeks, his boys spent 38 days in the NICU before coming home. Thankfully there were no major complications, they just needed to get caught up.

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4 Critical Mistakes Expectant Twin Parents Make

What to Prepare This Week

When Mom is 31 weeks pregnant with twins, talk in detail about the logistics of when the twins are born. You’ll want to take lots of pictures at delivery and with the newborns. Even fraternal twins look very similar as swaddled newborns in identical blankets. Plan now how to tell your newborn twins apart in pictures.

Your Fellow Parents at 31 Weeks Pregnant with Twins

Andrea R. – “Feeling pretty good minus swollen feet. I’m done working now so I can slow down and keep babies in as long as possible!”

Luke C. – “31+1 today, expecting identical girls, they’re our first babies! Mother is feeling fatigued now, swelling of the hands and feet, the girls are transverse at the moment so very uncomfortable for Mum, they’re currently 3lb 6oz and 3lb 9oz which is great, expecting to go to 36 weeks.”

Nelson D – “Slightly swollen feet after Mom’s current half days of bed rest. Some tightness in the lower abdomen as the kids seem to be wrestling each other in there and sleeping on her side has been a bit awkward”

(RELATED: Don't reinvent the twin parenting wheel. Get my 7 Things Every Dad of Twins Needs to Know.)

Dad’s Thoughts

By the time Mom reaches 31 weeks pregnant with twins, you might have concerns about what will happen if your babies are born early and spend time in the NICU. This is particularly concerning when you’ve got other kids at home. Plan out your ideas of how to balance older children at home and spending time in the NICU.

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Still wondering how to prepare for your twins? I cover specific things you should know and prepare for in my Dad’s Guide to Twins book. Learn more about the book here.

4 Critical Mistakes Expectant Twin Parents Make

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Sources: When You’re Expecting Twins, Triplets, or Quads: Proven Guidelines for a Healthy Multiple Pregnancy by Dr. Barbara Luke and Tamara Eberlein and Babycenter’s Average fetal length and weight chart

Further Reading

Dad's Guide to Raising Twins book
Don't forget to pick up a copy of the definitive guide to raising twins. "Dad's Guide to Raising Twins" was written for fathers of twins to help guide you through the first several years with twins. Click here to learn more about the book and get your copy.

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