The effect of intrauterine growth on leukocyte telomere length at birth.

Telomeres are specialized nucleoprotein structures located at the ends of chromosomes, which play a crucial role in genomic stability. Telomere shortening has been proposed as a biomarker for the onset of age-related diseases. This study aimed to determine whether restricted or increased intrauterine growth affects leukocyte telomere length (LTL) at birth. One hundred sixty-five ( = 165) full-term neonates participated in the study. Fetuses were classified as intrauterine growth restriction (IUGR,  = 21), large-for-gestational-age (LGA,  = 15), or appropriate-for-gestational-age (AGA,  = 129), based on customized birth-weight standards. Mixed arteriovenous cord blood samples were collected for isolation of leukocyte DNA. The LTL was measured using multiplex monochrome quantitative real-time PCR and telomeric restriction fragments through Southern blot analysis (terminal restriction fragment [TRF]). Despite differences among groups in birth weight, length and head circumference, LTL did not differ among AGA (6.78 ± 0.58), IUGR (10.54 ± 1.80), and LGA (11.95 ± 2.42) neonates ( = .098). Cord blood IGF-1 and IGFBP-3 concentrations were higher in the LGA group. LTL positively correlated with birth length ( = 0.176,  = .032). Intrauterine growth does not seem to affect LTL at birth. Further studies, comprising a larger sample size of IUGR, LGA, and AGA neonates, are required to determine whether growth at birth influences LTL.