Maternal telomere length is shorter in intrauterine growth restriction versus uncomplicated pregnancies, but not in the offspring or in IVF-conceived newborns

The study aimed to determine whether IVF or intrauterine growth restriction (IUGR) result in short neonatal telomeres, which could explain the higher risk of cardiovascular and metabolic disease described in these populations.

This was an observational, analytical, cross-sectional, prospective study with controls in a tertiary hospital. The main outcome was to determine the leukocyte telomere length in 126 newborns and their mothers (n = 109). Newborns were conceived spontaneously or by IVF, and uncomplicated and IUGR pregnancies were studied. Telomere lengths were measured using high-throughput telomere quantitative fluorescent in-situ hybridization.

There was no difference in average telomere length between newborns conceived by IVF or those with IUGR and spontaneously conceived healthy newborns (P = 0.466 and P = 0.732, respectively); this remained after controlling for confounders (P = 0.218 and P = 0.991, respectively). Mothers of newborns with IUGR had a shorter average telomere length than women with uncomplicated pregnancies (P = 0.023), which was confirmed after controlling for age, body mass index and smoking habit (P = 0.034).

The results support the safety of IVF and IUGR in terms of the postnatal health of the newborns. The shorter telomeres of IUGR mothers may represent a higher cardiovascular risk, which would have clinical implications under the stress of pregnancy in otherwise healthy adults.