Early language development is key to later communication skills, social interaction, and academic success. A new meta-analysis by the University of Zurich has found that, on average, preterm infants show weaker language abilities than full-term children in the first 18 months of life.

Roughly one in ten babies worldwide is born before 37 weeks of pregnancy – a birth considered preterm. These infants are biologically less mature at birth and face a higher risk of developmental delays in various domains. Previous studies have shown that preterm children tend to score lower on language assessments during kindergarten and school age. But do these differences already emerge during infancy?

Differences in Language Comprehension and Expression
Researchers at the University of Zurich set out to answer this question by examining whether language differences can be detected within the first 18 months of life. For their meta-analysis, they reviewed 21 studies from nine countries, covering more than 1,800 children. The findings revealed that preterm infants between the ages of 3 and 18 months scored lower on both language comprehension and expression compared to their full-term peers.

Especially Evident in Very Early Preterm Births
“These results should be interpreted with caution,” says lead author Miriam Löffler. “The preterm infants in the studies we analyzed were, on average, born at 30 weeks of gestation.” In reality, about 75 percent of all preterm births occur later, between 34 and 37 weeks. The researchers found that the earlier the birth and the lower the birth weight, the weaker the child’s performance in language comprehension. “In a more representative sample, these differences might be less pronounced,” explains the developmental psychologist.

Monitoring and Supporting Early Language Development
The meta-analysis highlights the importance of identifying potential language delays within the first months of life. While many early signs may resolve over time, they can still indicate future developmental risks. That’s why early language development should be systematically monitored during routine health check-ups – especially in preterm infants – and supported with targeted interventions when needed.
“Parents also play a vital role in fostering their child’s language development,” Löffler emphasizes. “Talking frequently with their baby from the very beginning, responding to their sounds, or looking at books together all help lay essential foundations. If there are concerns, it’s wise to consult a pediatrician or a speech-language specialist early on.”

Contact
Miriam Löffler
University of ZurichDepartment of Psychology
Developmental Psychology: Infancy and Childhood
Email: miriam.loeffler@jacobscenter.uzh.ch