Effects of preterm birth reach into second generation

Research at the University of Auckland’s Liggins Institute has shown that adults, particularly men, who were born preterm are fatter than those born at term.

The study, just published in the science journal PLOS ONE, found that men in their mid-thirties who were born before 37 weeks’ gestation were on average 20 kg heavier than a matched group born at full term. The preterm group also had significantly increased BMIs, a higher proportion of abdominal fat and less favourable lipid profiles.

In turn, children born at term to parents (both male and female) who were born preterm tended to have more body fat, with a greater distribution of abdominal fat, compared with the children whose parents were born at term.

One of the study authors, Liggins Institute Associate Professor Paul Hofman, said there is considerable evidence that preterm birth is associated with abnormalities in growth, body composition and metabolism during childhood. However data are scarce for adult survivors and almost non-existent for their children.

“In this study we set out to investigate whether the changes seen in childhood persisted into adulthood and if they could also be seen in the next generation,” said Dr Hofman.

“Being over-weight or obese, particularly when combined with a high proportion of abdominal fat, is associated with a number of long-term health problems, including diabetes and cardiovascular disease. Our data suggest that survivors of preterm birth (more than 10% of all births world-wide) may suffer some long-term adverse health effects,” he said.

“Importantly, we have seen the changes in body composition and fat distribution (and potential health risks) being passed to a second generation, regardless of whether the mother or father was born preterm.

“Our study adds weight to the considerable body of evidence that many adult health problems have their origins before conception and birth and in the early postnatal period. While preterm birth may have a number of causes, it emphasises the importance of good pre-pregnancy health and nutrition for all prospective parents and excellent antenatal care throughout pregnancy,” added Dr Hofman.

The study is one of a number that have followed the development of babies born during a world-famous clinical trial conducted at Auckland’s National Women’s Hospital in the early 1970s by Professors Graham Liggins and Ross Howie. That trial was the first to show that giving steroids to women in premature labour vastly improved the survival chances of babies born preterm.

A related study on the same group of subjects was published last year in the journal Diabetes. It showed that adults who were born even moderately preterm have a greater risk of developing type 2 diabetes than those born at term. However it did not appear that the risk was passed on to their children if the children were born at term.

The changes in body composition observed in the current study suggest on-going longitudinal studies will be necessary to define the full impact and health relevance of preterm birth for future generations,” said Dr Hofman.

The research was supported by grants from Gravida: National Centre for Growth and Development and the Australasian Paediatric Endocrine Group.
The paper: “Increased Adiposity in Adults Born Preterm and Their Children” is available on-line here.

Mathai S, Derraik JDB, Cutfield WS, Dalziel SR, Harding JE, Biggs J, Jefferies C, Hofman PL Increased Adiposity in Adults Born Preterm and Their Children
PLOS ONE 2013, 8, e81840

Leading scientists and communicators from the Liggins Institute will join with community leaders to discuss the ways in which the Institute’s research is being translated into clinical care and better understanding of the long-term effects of the early-life environment at a public forum on 29 November.

Womb to Wellness – a conversation with our community
29 November 2013 11.15am to 1.15pm
University of Auckland Grafton Campus, 85 Park Road, Grafton
Details: www.liggins.auckland.ac.nz
 

Media contact: Pandora Carlyon, Communications Manager
Liggins Institute. +64 9 923 2305; p.carlyon@auckland.ac.nz