Most adults born very premature go on to thrive, but one in five face lasting economic and social struggles

The majority of adults born very preterm or at very low birth weight go on to build stable, satisfying lives in their mid-30s, but around one in five face a cluster of lasting difficulties with employment, romantic relationships and friendships, according to new research published in JAMA Paediatrics.

The Bavarian Longitudinal Study led by Professor Dieter Wolke at the University of Warwick, followed 416 adults, 214 of whom were born very preterm (before 32 weeks) or at very low birth weight (under 3.3lbs/1.5kg), from birth in the mid-1980s through to the age of 34, making it one of the longest-running cohort studies of its kind internationally.

Using detailed life-course interviews covering risk-avoidance, wealth, and relationships with parents, partners and friends, researchers identified three distinct patterns of adult functioning:

•             Optimal functioning (full term: 74%; preterm 56%): doing well across all areas of life.

•             Moderate functioning (full term: 24%; preterm: 26%): generally doing well, but with romantic struggles and lower economic success.

•             Low economic and social functioning (full term: 1.5%; preterm: 18%): struggling with money, friendships and partnerships.

Dr. Elif Gönen, Department of Psychology, University of Warwick said: “Our data show that just over half of those born very preterm or with very low birth weight showed optimal functioning across risk avoidance, wealth, and social relations while 18% showed low functioning compared to 1.5% of full-term babies. Those adults in the low-functioning group rated their life satisfaction very much lower than the other groups.”

Childhood IQ emerges as the key, but modifiable, factor

To understand what shaped these adult outcomes, the research team examined a wide range of childhood influences, including preterm birth itself, sex, self-control, parenting quality, peer relationships in primary school, family income and background, family climate, and the parents’ own relationship.

Several factors on their own were linked to how well people fared as adults, including being born at term, how much effort a child put into tasks, and positive parenting. But when all factors were considered together, only one stood out as a robust, independent predictor: childhood IQ at age 8.

A 15-point increase in childhood IQ, roughly the average gap seen between children born very preterm and their full-term peers, was associated with a 79% reduction in the odds of poor economic and social functioning in adulthood.

Professor Dieter Wolke, Department of Psychology, University of Warwick said: “For decades, the question we’ve been asked most is whether children born very preterm are destined to struggle for life. This study gives a hopeful and nuanced answer. Most people born very preterm are getting on well in their thirties, building careers, relationships and friendships much like everyone else. But there is a substantial minority who continue to face real difficulties, and they tell us their lives feels hard and not very satisfying. What’s striking is that the strongest thread running through all of this is childhood cognitive ability, and that isn’t set in stone. It responds to the environment a child grows up in. Supporting children’s thinking and learning skills early on, through positive parenting and good schooling, could make a real difference to how their lives unfold decades later.”

Why this matters

With survival rates for very preterm and very low birth weight babies now around 95%, an increasing number of people who once might not have survived infancy are now reaching adulthood, and researchers say understanding what helps them thrive is a growing public health priority.

The findings suggest that rather than focusing solely on managing the risks associated with preterm birth, investment in early cognitive development through parenting support and school-based interventions could have long-lasting benefits, for children born preterm and full-term alike, because these are areas where meaningful change is possible.