Developmental Delays in Premature and Late Preterm Babies

A Summary of the article by Maureen Salamon, HealthDay that appeared on USAToday.com February 2011

Recent studies seem to indicate that even babies who are considered “late preterm”, meaning they were born between 34-37 weeks gestation have more developmental delays than full term babies and in turn this can affect their later progress in school.

In a study that was reported online February 14, 2011 in the Journal of Pediatrics, researchers in Boston concluded after analyzing data on 6,300 full term and 1,200 late preterm babies that:

  1. Late preterm babies were 52% more likely to exhibit severe cognitive delays and 43% more likely to show milder delays in their cognitive skills.
  2. Late preterm babies were 56% more likely to show severe motor delays and 58% more likely to show mild motor delays.

In the past babies born between 34-37 weeks gestation were simply considered small, but thought to be much like their full term peers and not at all considered to be preterm babies.

According to this article’s statistics, 13% of all births are preterm in the USA. But, late preterm births have increased 25% since 1990 and now account for 7-9% of all births.

This new data has huge implications for us as early intervention providers, especially since it was cited that the majority of these late preterm babies receive little or no developmental follow-up after birth.

One organization also reported that between 5-40% of all births were elective deliveries, meaning babies were being born early for no apparent medical reason. Just an extra 1-2 weeks in the womb can make a world of difference.

Some other interesting conclusions of this study were that the brain of a baby born at 34 weeks gestation weighs 35% less than it would in a full term infant at 40 weeks.

The researchers also noted that social factors and gender had the greatest impact on mental scores. But, gestational age had the most impact on motor delays. Boys were also found to have more delays than girls.

Limitations of this study included a lack of information on possible newborn medical complications and the possible weaknesses of infant developmental testing to determine delays, but the researchers felt their findings were consistent with other current studies on late preterm infants. The study also found that late preterm infants are at higher risk for respiratory problems, worse academic performance in school and even later school suspensions.

“There’s a reason why normal gestation is 40 weeks,” said Dr. Marty Ellington Jr., chairman of the department of pediatrics at Lenox Hill Hospital in New York City. He also cited that these late preterm infants are not getting automatically referred to early intervention like the very premature infants do.

Dr. Ellington indicated that the gender and medical issues of late preterm babies can’t be changed, but that their referral to developmental follow-up and access to early intervention services may help them avoid future issues with academics later on in life.