London, Jul 10 (IANS): Researchers have revealed that bacteria in meconium -- the earliest stool of an infant -- may indicate their risk of obesity.

Meconium is composed of materials ingested during the time the infant spends in the uterus. The study, published in the journal Pediatric Obesity, Obesity found that the types of normal bacteria found in the meconium may predict an infant's likelihood of later developing obesity.

Several reports have shown that the firstapass meconium hosts a diverse microbiome, but its clinical significance is not known.

"We designed a prospective populationabased cohort study to evaluate whether the meconium microbiome predicts subsequent growth in children," said study authors from the University of Oulu in Finland.

In the study of 212 newborns, children who became overweight at three years of age differed in their meconium bacterial makeup from those with normal weight, having a higher proportion of bacteria in the Bacteroidetes phylum (29 per cent versus 15 per cent).

The findings showed that the microbiome of the first pass meconium predicted subsequent overweight at the age of three years. "The concept of the fetal microbiome is controversial and the colonisation process after birth is better understood than the possible fetal colonization," said study researcher Katja Korpela from the University of Oulu.

"However, there are many prenatal factors affecting the microbial composition of the baby's first stool, such as the mother's use of antibiotics during pregnancy and biodiversity of the home environment during pregnancy," Korpela added.

In conclusion, the research team showed that the microbiome of the first pass meconium, formed during pregnancy, was associated with later overweight in the same children at the age of three years.

The results emphasize the importance of investigating maternal and prenatal factors when considering the pathogenesis of paediatric obesity."It is very interesting that the microbiome formed before birth is possibly linked to a child's subsequent weight status," the study authors wrote.