Overweight and obesity are growing worldwide problem including in women in reproductive age. Maternal overweight and obesity are well-known risk factors that could affect several mental and physical effect to their babies.

New study found that maternal obesity has linked shorter newborn telomere size by checking cord blood and placental telomeres. Telomere is a tandem repeatable nucleotide sequences located at end of each chromosomes and gradually shorten their length every replication. Telomere length is considered as bio-clock of mankind because they maintain genomic stability and protect chromosome inside cells.

The researchers have analyzed correlation between pregnant women’s obesity and telomere length of newborn from cord blood or placenta from 768 mother-newborn pairs. Because DNA quality was bad to study, this group finally used data both 743 couples from cord blood and 702 pairs from placental telomeres. To check length of telomere, they collected and extracted cells to get chromosomal DNA. After that they measured average length of telomere by modified quantitative real-time PCR and calculated using qBase software.

They found that 1 point BMI (Body Mass Index) increase of pregnant women showed shortening 50 base pair telomere of newborn. 50 base pair length of telomere is considered as one year bio-clock of adult telomere. Co-author Tim S. Nawrot, Ph.D from Environmental science, Hasselt University, Belgium said “Our results add to the growing body of evidence that high maternal BMI impacts fetal [DNA] programming, which could lead to altered fetal development and later life diseases”.

This finding only shows correlation between telomere length and maternal obesity. Further study needs to be conducted for proving which factors make shorten telomere during pregnancy. However, this study suggests that pre-pregnancy healthy control is important for molecular longevity for newborn.