In a meta-analysis — a study compiling data from multiple studies — published on January 26the Danish epidemiologist Johan Vinther and his colleagues, compared the medical records of 250,000 people born between 1985 and 2017. These records included data on pregnancy and follow-ups on weight or height, spread over several years.
body mass index (BMI) is obviously not the only possible indicator for comparing the growth of these two groups, but it is a relevant approximation, justify the authors.
It appears from these data that, although babies born before the 37th week of pregnancy were more at risk, in their childhood, of having a lower BMI than others, this difference had faded once they reached adolescence.
We are talking about an average here, and that applies only to rich countries.
It should be noted that knowledge of the long-term impacts of premature birth is still very incomplete. One of the reasons is that, until the 1970s, the chances of survival for a baby born before the 37th week of pregnancy were very slim. The other is that it is difficult, and sometimes tricky, to follow thousands of premature infants for several years, even into adulthood, in order to have them undergo regular learning and behavior tests, with all the uncertainty this places on them and their parents. In 2015, a magazine report Nature further underlined how “we are only beginning to understand the effects of premature birth”.