Early developmental trajectories of preterm infants.
Preterm birth severity predicts widening developmental gaps by 18 months—use Mullen trajectories to flag EPT/VPT infants for early intervention referral.
01Research in Context
What this study did
The team tracked 200 babies born early. They used the Mullen Scales at 6, 12, and 18 months.
They split infants into three groups: extremely, very, and moderately preterm. Full-term babies served as the baseline.
Doctors wanted to see how early birth hurts thinking, talking, and moving skills over time.
What they found
Extremely and very preterm babies slid further behind each visit. By 18 months they scored 10-15 points lower on every Mullen scale.
Moderately preterm infants lost fewer points, yet still fell below the norm.
The gap widened fastest in language and fine-motor areas.
How this fits with other research
Velikos et al. (2015) saw the same delays at 12 months using the Bayley-III. Maya’s 18-month follow-up shows the slide continues, so the Bayley snapshot was an early warning, not a fluke.
Kuang et al. (2025) took the idea further. They fed BSID-III trajectory data into a computer model and predicted ASD risk with a large share certainty. Maya’s paper sets the stage; Chen shows you can act on those curves.
Tang et al. (2025) looked at preterm kids without major diagnoses at school age. They still showed subtle anxiety and attention issues. Together the studies trace a line: early low scores forecast later struggles, even when labels like autism are absent.
Why it matters
You can spot trouble before it snowballs. Plot Mullen scores at each well-baby visit. If an extremely preterm child flattens or drops between 6 and 12 months, start speech or OT right then. Don’t wait for a firm autism label; the trajectory is the red flag.
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Join Free →Graph each preterm baby’s Mullen t-scores over time; if any line dips or plateaus, fax the referral for services that day.
02At a glance
03Original abstract
BACKGROUND AND OBJECTIVES: Preterm infants are at risk for neuro-developmental impairments and atypical developmental trajectories. The aims of this study were to delineate early developmental trajectories of preterm and full-term infants. METHODS: The cognitive, language, and motor development of 149 infants - 19 extremely preterm (EPT), 34 very preterm (VPT), 57 moderately preterm (MPT), and 39 full-term (FT) - was evaluated using Mullen Scales at 1, 4, 8, 12, and 18 months. Mixed models were applied to examine group differences. Gender, maternal education, and neurobehavior were included as predictors of developmental trajectories. RESULTS: The EPT and VPT infants achieved significantly lower scores than the FT infants in all domains, with a significantly increasing gap over time. The MPT infants' trajectories were more favorable than those of the EPT and VPT infants yet lower than the FT infants on the Visual Reception, Gross, and Fine Motor subscales. Male gender and lower maternal education were associated with lower scores that declined over time. Abnormal neonatal neurobehavior was associated lower Mullen scores and with less stability in scores over time. CONCLUSIONS: The EPT and VPT infants were found to have disadvantages across all domains. The MPT infants revealed more favorable developmental trajectories yet displayed vulnerability compared to the FT infants. Gender, maternal education, and neonatal neurobehavior are important in predicting the developmental outcomes of preterm infants.
Research in developmental disabilities, 2018 · doi:10.1016/j.ridd.2017.10.018