Study Says Birth Weight Predicts A Child's Intellect. Is This True?

Study Says Birth Weight Predicts A Child's Intellect. Is This True?

However, researchers did say that they need to do more research to verify these claims, as there are a lot of other things that can influence a baby's intelligence.

A baby’s weight is one of the first things that is recorded soon after birth. This birth weight becomes the child’s initial reference point to track all future weight gain and loss that help track physical development. Now, a new study suggests that birth weight is also related to intelligence through life later on. We’ve also included tips for low birth weight babies management later on.

Low birth weight linked to lower intelligence well into adulthood, says study

Results from a new longitudinal study from Denmark claims that below-average birth weight is linked to a lower intelligence quotient (IQ) well into adulthood.   

Researchers found that the differences in IQ — when comparing underweight babies and their normal counterparts — didn’t change much as they grew up. Even among the babies born within the “normal weight” bracket, newborns who were heavier still had slightly higher IQ as they grew up.

Trine Flensborg-Madsen, the lead study-author from the University of Copenhagen, said that they discovered “the association between birth weight and intelligence is stable from young adulthood into midlife.” 

According to Flens-borg-Madsen, “There are long-term cognitive consequences of birth weight that do not diminish.”

low birth weight babies management

A recent study claims that birth weight is related to a baby’s future intellectual ability, says scientists. | Image Source: Stock Photo

What the study found

In the study, researchers analysed data from roughly 4,700 babies in Copenhagen between 1959 to 1961. They looked at birth records and their scores from IQ tests which these individuals attempted when they were 19, 28 and 50 years old, too.

They categorised babies by weight, that is:
  • weighing below 2.5 kg, or underweight
  • between 2.5 kg to 3 kg
  • weighing from 3 kg to 3.5 kg, which was considered normal
  • between 3.5 kg to 4 kg
  • weighing over 4 kg, or overweight

The researchers report in the Journal Pediatrics that birth weight was deeply linked to intellect in their IQ tests conducted at 19, 28 and 50. 

The link still held true after researchers took into account other things which may affect intellect.

low birth weight babies management

The trend was also observed in babies who are of normal birth weight, so more research is needed to verify their results. | Image Source: Stock Photo

More research needed, says scientists

However, according to the authors, weighing below-average from birth isn’t a good explanation for the link. That’s because the same pattern was also observed in newborn babies who were delivered with healthy weights.

Furthermore, the experiment wasn’t especially formulated to verify if below-average birth weight  directly leads to lower IQ scores, or if larger babies are actually more clever.

The study also didn’t take into account many other possible factors that could affect the child’s intelligence, like:

  • what their home environment was like
  • their mum’s stress levels
  • how smart their parents were.

All these could affect the infants’ IQ score in the future. 

According to Dr. Susan Shenkin, a scientist from the University of Edinburgh who wasn’t part of the team, parents need not fret so much at this discovery.
In fact, Shenkin says that many years ago, there was less focus on prenatal care — which could  affect how infants in the study grow up: they could have developed differently compared to  babies nowadays.

“The brain develops rapidly before birth, and therefore lower birth weight may reflect a poorer environment for brain growth,” says Shenkin. “We still can’t say whether low birth weight ‘causes’ lower cognitive ability test scores.”

Low birth weight babies management tips for new mums

Mums, we know you’re concerned if your baby has low birth weight. According to Stanford Children’s Health, there are many ways to estimate your child’s birth weight before delivery.

However, after your little one is born, your doctors will weigh them and advise you appropriately. If your little one is severely underweight, additional treatment may be recommended, including:

  • Tending to them in the Neonatal Intensive Care Unit, or NICU

  • providing them beds with adjustable temperatures

  • providing special methods to feed them, such as via a tube directly connected into to your little one’s stomach (if they are unable to suck), or by using an intravenous (IV) line 

If all goes well, your little one can be discharged. But here comes the hard part: how do you know you’re on the right track? Here are some low birth weight babies management tips to get you started.

Low birth weight babies management tip #1: How you feed them matters

To breastfeed or give them formula? There are a few things you need to know about both when it comes to birth weight.

Babies feeding on formula are likelier to pack on weight faster than their breastfed counterparts. In fact, it’s possible for formula-fed babies to put on too much weight. After all, formula is more concentrated than breastmilk and parents usually expect their babies to empty the whole bottle.

Dr Jack Newman is well known as a breastfeeding expert and paediatrician. According to him, excessive weight gain is less of a concern for breastfed babies, as they can stop sucking when they’re full (rather than finishing off the bottle). Thus, they can self-regulate the amount of milk they drink.

“I wouldn’t worry about rapid growth in a breastfed baby who is content and healthy,” says Dr Newman.

low birth weight babies management

Low birth weight babies management tip: check their diapers often. Are they wetting them enough or passing the right stools? | Image Source: Stock Photo 

Low birth weight babies management tip 2: Check those early diapers as much as you can

During the first three days after being born, your baby will shed dark stools, called meconium. By the third or fourth day though, the stools should be soft and yellow (if breastfed) or darker and firmer (formula-fed).

If you don’t notice these changes, experts say that your little one might not be getting enough milk.

Another red flag for inadequate milk is that your little one isn’t wetting his nappies enough each day. Generally, two-day-old newborn babies will produce two to three wet diapers a day. However, by the time they become seven days old, they should be producing about six to eight wet diapers.

If you’re concerned because your baby hasn’t been wetting his nappies enough, or if you do find something wrong with his stools, please consult your paediatrician immediately.

Parents, we hope that this article about low birth weight babies management has been helpful to you. If you liked this article, please share it on for other parents in Facebook!

References: Reuters, Stanford’s Children Health

Also read:

“Is my baby’s weight normal?”: A guide to newborn weight loss and gain

Study reveals that early pregnancy weight gain impacts baby’s size

Why is my child losing weight?


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