Recognition of a sequence: more growth before birth, longer telomeres at birth, more lean mass after birth.

BACKGROUND

Telomere length at birth is a major determinant of telomere length in late adulthood. However, the prenatal setting of telomere length is poorly understood. Individuals born large from non-diabetic mothers are at lower risk for later-life disorders than those born small, a feature of their longer health span being a higher lean mass that provides more muscle strength and that is already present in infancy.

METHODS

At birth, we studied leukocyte telomere length (by quantitative polymerase chain reaction) in 103 small-for-gestational-age, appropriate-for-gestational-age or large-for-gestational-age (SGA, AGA or LGA) infants born after uncomplicated, term, singleton pregnancies. All infants were breastfed for ≥4 months. At 2 weeks and 12 months, body composition was assessed by dual X-ray absorptiometry.

RESULTS

Telomere lengths were shorter in SGA newborns and longer in LGA newborns than in AGA newborns (P < 0.001), also after adjustment for maternal age, pre-gestational body mass index, gestational weight gain and gestational age. Telomere length at birth associated (all P ≤ 0.001) to birthweight (r = 0.50) and to both lean mass (r = 0.43) and fat mass (r = 0.48) at age 2 weeks, but only to lean mass at 12 months (r = 0.51).

CONCLUSION

Higher weight and longer telomeres at birth are followed by more lean mass in late infancy. Relatively large, breastfed infants from non-diabetic mothers may become models of how to make a healthy start.