Research shows all underweight babies may be at higher risk of childhood developmental complications – not just those with extremely low birthweights

Babies with mild to moderately small birthweight may face an increased likelihood of childhood developmental complications – and may need the same monitoring and support currently reserved for babies with low and high birthweights.

First-of-its-kind research led by Assistant Professor Abiodun Adanikin from Coventry University’s Centre for Healthcare Research studied more than 600,000 infants born after 37 weeks of pregnancy over a 12-year period.

Previous research focused on babies born below the 10th centile, but Assistant Professor Adanikin’s research shows developmental complications can also be found in those below the 25th centile.

The research analysed maternity and delivery records of children between two and three years old for complications including fine motor (the coordination of small muscles in movement with the eyes, including synchronisation of hands and fingers), gross motor (the movement and coordination of larger bodily parts), social and communication skills.

Findings revealed that those with birthweights between 10th and 24th centiles – weighing approximately between 2.5kg and 3kg – are around 20% more likely to have fine or gross complications and 17% more likely to have communication complications, in comparison to those born above the 25th centile.

To reduce the risk of these complications, Assistant Professor Adanikin calls for closer monitoring of mild to moderately small for gestational age (SGA)** babies. This is opposed to the most frequently used traditional approach of targeting prevention in only extremely low and high birthweights.

Although extremes of birthweight are known to be linked to childhood development, until now there has been no research that exclusively investigated the relationship between birthweight centiles across its range and subsequent childhood development in babies born after 37 weeks.

Previous studies have reported that babies born below the 10th centile are at the greatest risk of facing development complications, this new research extends that risk to babies born below the 25th centile.

Assistant Professor Adanikin said: “Though it is mostly unrecognised, babies who are mild-to-moderately small at birth may need closer monitoring and increased support to reduce the risk of developmental concerns.”

The study calls for reconsideration of the traditional birthweight thresholds used in clinical practice for defining low birthweight and suggests implementing early childhood monitoring and support for infants born from 37 weeks of pregnancy with lower birthweight centiles, to reduce the risk of childhood developmental complications.

Assistant Professor Abiodun Adanikin from Coventry University’s Centre for Healthcare Research

Assistant Professor Adanikin has combined background in medicine, public health, and epidemiology. He holds specialist qualifications in obstetrics and gynaecology and has about 15 years of clinical and research experience in the field of maternal and child health. He was recently a member of the World Health Organization Guideline Steering Group, where he co-edited two global maternal health guidelines. Currently, he works as an Assistant Professor at the Centre for Healthcare Research, Coventry University.

This project was funded by the Wellbeing of Women Research Grant.

The size of the baby assessed between conception and birth – babies born from 37 weeks of pregnancy