Congratulations, you are now 4 months pregnant with twins! That’s right, at 16 weeks pregnant with twins, you have just about made it to the 4-month mark.
Hopefully, you are enjoying the energizing effects of the second trimester “golden age” and have a successful16-week prenatal visit. I always looked forward to my prenatal visits because it made it feel like things I was checking off a box and getting closer to my due date!
The babies are growing more every day with exciting developments underway, and of course, your body is changing too.

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Twin Pregnancy Week 16 (4 months pregnant with twins)
At 16 weeks, you’re officially 4 months pregnant with twins! You’re getting so close. I know it’s hard, but you are doing great. Growing two humans is a lot of work.
Related —-> 7 Important Things to Consider When You Find Out You’re Having Twins!
Twin Pregnancy Symptoms at 16 Weeks
Backaches
An unfortunate reality of pregnancy, and especially twin pregnancy, is back pain. Your growing twin bump is going to put strain on your back. To alleviate the aches, be sure to stretch often (I say that, but instead of stretching, I collapsed on my couch, so you can follow my advice or you can follow what I actually did).
A pregnancy support belt will help tremendously with any lower back pain you may be experiencing.
Round Ligament Pain
These aches and pains are here to stay, unfortunately. Your muscles and ligaments are stretching out to make room for two little babies. And if that still feels surreal to you, it does for me as well!
Trust me when I tell you that these bath salts will make your body feel so much better. I’ve never watched so much Netflix in my life as when I was expecting twins. Every single night, I’d put my achy body in the bath and watch something (or read a book), and it gave me so much relief!
Loose Joints
Relaxin is a reproductive hormone produced by your ovaries and the placenta. It loosens and relaxes your muscles, joints, and ligaments during pregnancy to help your body stretch. Relaxin also helps your body prepare for delivery by loosening the muscles and ligaments in your pelvis (sou0rce: Cleveland Clinic)
They say that you shouldn’t feel your joints loosening, but I sure felt it in my hips. Not only were they constantly sore and achy, but they just felt unsteady, especially while walking up the stairs.
In fact, there were a few times when my hips actually gave out on me while I was carrying my toddler up the stairs. I managed to catch myself but it was definitely nerve-wracking!
Breast Swelling
You may start to notice that your boobs are bigger–often by several cup sizes! By the end of the second trimester, your breasts will be ready for breastfeeding.
Constipation
Because your uterus has expanded enough to put pressure on your intestines, you might find yourself constipated. Totally normal! The best thing to do is eat plenty of fiber-rich foods and drink plenty of water.
Something that helped me was drinking Natural Calm, a magnesium supplement every night. It is perfectly safe for pregnancy, but of course, consult with your doctor, as I am not a medical professional 🙂
And if you do start drinking Natural Calm, do not start with the full serving size! It says to start with 1/2 teaspoon, but I am ultra-conservative and started with 1/4 teaspoon.
Sensitive Eyes
Dry, itchy, watery are common at this stage too, especially if you’re prone to allergies! Consult your doctor to find out if any over-the-counter allergy meds might help.
Pregnancy Glow
Yes, thanks to hormonal changes, around 4 months is when most pregnant women experience the “pregnancy glow” which can really help you look your best during a time when you already feel your best!
For more tips to help you through your twin pregnancy, check out this post –> How to Survive a Twin Pregnancy

Twins Fetal Development at 16 Weeks
The babies are growing a lot–their eyes have developed considerably, moving side to side, and can detect light, even though they’re still closed. They can also hear your sound waves and will recognize your voice from birth, so keep talking to them!
Hair, eyelashes, and eyebrows are starting to grow and muscles and bones continue to develop. The liver and pancreas start working, taste buds start forming, and toenails appear!
(Sources: The Bump and What to Expect)
How Big Are Twins at 16 Weeks?
There is a lot of growth this week! Your babies are about 4.5 inches long and weigh an average of 3.5 ounces this week.
In fruit terms, your babies are the size of an avocado.
At my 16-week ultrasound, one baby was measuring at 16 weeks, 1 day, and the other twin was measuring at 15 weeks, 1 day. It’s very common for twins to be different sizes in utero, and not usually something to worry about unless the difference is extreme.
Wondering if you can prepare for twins on a budget? I have lots of tips!
Can I Feel My Twins Moving at 16 Weeks?
It is possible that you start to feel little kicks at 16 weeks with twins, but it isn’t super likely. I didn’t feel any movement until a tiny bit at 18 weeks, and it was my 2nd pregnancy. However, every pregnancy is different, so it may not be the case for you!
Feeling movement doesn’t happen any earlier for twin moms than it does for singleton moms, but the frequency will increase as you get further along for obvious reasons: twice the feet equals twice the kicks.
16 Weeks Pregnant with Twins Belly
Twin moms are definitely showing by this point and the pregnant belly growth only accelerates from here!
If you haven’t invested in maternity clothes yet, now is the time… along with some comfortable maternity and nursing bras to accommodate your growing breasts. Weight gain is common by this time, about a pound to a pound and a half per week.

Here is my 16 week twin bump! In case you couldn’t tell, I am in full-on maternity clothes at this point. I will link some of my favorites below.
16 Weeks Pregnant with Twins: my experience
Here is an excerpt from my twin pregnancy journal at 16 weeks.
I’m feeling tired and achy. I’m trying to get things done around the house, take care of Theo, go to work, and also take it easy? It feels impossible. I guess that’s a reality of having twins.
I’m struggling to find a balance between getting things done and taking it easy. I feel like I could take a nap every day while Theo is napping, but that’s my only time to prep dinner, do laundry, and a million other things.
I hope that I’m just overdoing it this week, and that the aches and tiredness I’m feeling isn’t here to stay, because for crying out loud, I am only 16 weeks! Just barely four months pregnant! It’s crazy how much this pregnancy is taking out of me. (hint: the tiredness and body aches WERE there to stay, for the rest of my pregnancy.)
Things to Purchase When You’re 4 Months Pregnant with Twins
- Bra extender: you will eventually want to buy nursing bras, but not until later on in your pregnancy, as your breasts still have a way to grow. A bra extender is a clever solution to make your regular bras last a few more months.
- Maternity Pajamas: everything by this brand is so lovely. This is another pair if you prefer long pajamas.
- Magnesium bath soak: This will feel delightful to your achy body.
- Maternity leggings: These were my favorites for a budget pair. These were my favorites for a splurge.
- Pregnancy pillow! I loved mine sooo much.
- Belly butter: Even if you don’t care about getting stretch marks, belly butter and belly oil will soon be a relief. The skin around your belly might become dry and itchy as it stretches out!
- It is also time to invest in some maternity clothing past maternity leggings. Things change out seasonally, but I have always had really good luck at Target and Old Navy for jeans, tops, and dresses. I prefer overbelly jeans vs underbelly ones! Those just fall down. Another way to extend your wardrobe is to buy a few nice, solid-colored tanks or t-shirts and wear them with open cardigans/jackets that don’t have to be maternity.
- This is a 3-pack of maternity tanks that are perfect for layering. Prefer long sleeves? Try these!
My whole list of products for your entire twin pregnancy: –> Twin Pregnancy Essentials
Twin Pregnancy Health Tips: 16 Weeks
- 4 Month Prenatal Visit: 16 weeks marks 4 months of pregnancy, which means it’s time for a checkup! You’ll have a urine test to ensure you don’t have gestational diabetes or preeclampsia. Since twin pregnancies come with greater risk, it’s important to take extra care and test for birth defects or genetic disorders early on. But don’t fret! Healthy babies are the rule, not the exception.
- You might have an ultrasound too, but most wait until between 18-22 months, which is far enough along to determine the sex of your babies.
- Eat plenty of nutrient-rich snacks… when you’re carrying twins, you need about 600 extra calories a day, so make sure it’s (mostly) a healthy diet!
- Make lists and set reminders
- Buy comfy bras and cotton underwear (increased discharge is another common symptom!)
- Keep taking those prenatal vitamins and make sure you’re getting plenty of iron and folic acid!
Twin Pregnancy To-Do List
- Schedule your 20-week prenatal visit.
- Schedule your 18-22 week Anatomy scan (some offices combine it with your 20-week visit)
- Start looking for baby names!
- Start brainstorming for twin baby shower ideas… the best time to have one is during your third trimester, but it never hurts to be prepared!
- You should be making headway on your twin registry.
- Start planning your twin nursery! One of my favorite things!