Actual Vs Adjusted Age Newborn Twin Babies All The Small Things Uncropped
Source: TwinsyTwins

Statistically speaking, pre-term birth is the outcome for approximately 55 percent of twin pregnancies (this number is between six and 10 percent for pregnancies with a single baby).

Multiples who are born before 37 weeks' gestation are considered premature, while a full-term gestation period for a singleton pregnancy is 40 weeks.

Most twins end up being delivered around the 36-week mark, either by spontaneous delivery or a planned induction or C-section, and, of course, some multiples are born much sooner.

Actual Vs Adjusted Age Milestone Standing
Source: TwinsyTwins

Being born prematurely can affect when babies reach major milestones, from your little ones' first time smiling, to sitting up unassisted, to standing, scooting, walking, and talking.

Babies who are born early still have important developing to do that they didn't get a chance to finish while they were in utero, and the depth of development that remains once they are born depends on how early they arrived.

This is why it's crucial for parents and pediatricians or primary care practitioners to track both the actual age of your twins and their adjusted age, too.

What is the difference between actual age and adjusted age?

Actual Vs Adjusted Age Newborn Twin Baby Thinking
Source: TwinsyTwins

Your babies' actual age is their age based on the date they were actually born. So, one week after the date on which they were born, their actual age would be one week old. That's easy enough to keep track of.

Their adjusted age (also known as their corrected age) is determined by how early they were born. To figure out their adjusted age, you start with their actual age in weeks, and then you subtract the number of weeks they were born early. This will give you your twins' corrected age.

So, for example, my twins were born 6.5 weeks early, so when they were 12 weeks old ( their actual age), their adjusted age was only 5.5 weeks old.

This is a significant factor to consider when you think of the developmental differences between a three-month old baby and an infant who is only 1.5 months old.

This is a significant factor to consider when you think of the developmental differences between a three-month old baby and an infant who is only 1.5 months old.

To put the sorts of differences you might encounter into perspective, a twin baby who is born six or seven weeks early still has a LOT of important developing to do, which they now have to do outside of the womb.

At 30 weeks' along, your babies' brains and eyes are still developing, with their vision still continuing to develop until they reach 34 weeks along.

At 30 weeks' along, your babies' brains and eyes are still developing, with their vision still continuing to develop until they reach 34 weeks along.

At 32 weeks' gestation, their skull bones are still not solid nor fused together, and their lungs are not yet quite completely ready for breathing on their own. By this point, the rest of their major organs (aside from the lungs) are now fully formed, and their skin is no longer transparent, having just finally turned opaque.

By 33 weeks' along, your twins' digestive systems are fully working on their own, and from this point on and up until delivery, they continue growing and putting on weight.

But if your multiples are born before this point, they have a lot of integral developing to continue doing once they're no longer in utero.

Why is it important to track both the actual and adjusted ages of your preemies?

Actual Vs Adjusted Age Newborn Twins Stretched Out Sleeping In Bassinet Basket
Source: TwinsyTwins

It's important to track both the actual and adjusted ages of your multiples if they were born prematurely (before 37 weeks' gestation) because they may need a little bit more time to reach developmental milestones than a baby who was born at full-term gestation.

To put it bluntly, babies who are born early have to spend their first few weeks of life (however many weeks before 37 they were born) catching up on the development and growth that would have taken place if they'd stayed inside the womb a few weeks longer.

Actual Vs Adjusted Age In Utero Vs Newborn
Source: TwinsyTwins
This is my Baby A in utero vs. his first week at home after his two-week stay in the neonatal intensive care unit after being born six-and-a-half weeks early.

This means that, as a result of their pre-term birth, your multiples may very well take longer to reach certain milestones for the first several months of their lives.

Your children's pediatrician or primary health care provider will take into account your twins' adjusted age when measuring their growth, recording their development, and monitoring when they reach certain milestones.

And they will bear their prematurity in mind if there are delays in those first couple of years. Most premature babies are given the benefit of the doubt when it comes to these scenarios (of course, if you have major concerns about any developmental milestones, bring them up with your pediatrician at their next wellness check).

Most toddlers catch up to where they should be by the time they turn two years old, and, from that point on, doctors will drop the adjusted age and just go by your little ones' actual age.

What's their age, again?

Actual Vs Adjusted Age Preemie Twin Curled Up Like In Uterojpg
Source: TwinsyTwins

From smiling, to sitting up unassisted, to standing, scooting, walking, and talking, prematurity can affect when babies reach major developmental milestones.

The depth of development that remains once they are born depends on how early they arrived. Every baby is different on how quickly they catch up from their adjusted age to their actual age and its corresponding expected development.

This is why it's important for parents, caregivers, and pediatricians to keep track of both the actual age of your twins and their adjusted age, too.

In due time, your little ones will catch up and you'll never know they were born prematurely.

Were your twins born prematurely? How early did they arrive? Did you find it affected their milestones? Let us know in the Comments section below.

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