Background:
Leptin is a
hormone regulating lifetime energy homeostasis and metabolism and its concentration is important starting from prenatal life. We aimed to investigate the association of perinatal
leptin concentrations with growth trajectories during the first year of life. Methods: Prospective, longitudinal study, measuring
leptin concentration in maternal plasma before delivery, cord blood (CB), and mature breast milk and correlating their impact on neonate’s bodyweight from birth to 1 year of age, in 16 full-term (FT), 16 preterm (PT), and 13 intrauterine growth-restricted (IUGR) neonates. Results: Maternal
leptin concentrations were highest in the PT group, followed by IUGR and FT, with no statistical differences among groups (p = 0.213). CB
leptin concentrations were significantly higher in FT compared with PT and IUGR neonates (PT vs. FT; IUGR vs. FT: p < 0.001). Maternal milk
leptin concentrations were low, with no difference among groups. Maternal
leptin and milk concentrations were negatively associated with all the neonates’ weight changes (p = 0.017 and p = 0.006), while the association with CB
leptin was not significant (p = 0.051). Considering each subgroup individually, statistical analysis confirmed the previous results in PT and IUGR infants, with the highest value in the PT subgroup. In addition, this group’s results negatively correlated with CB
leptin (p = 0.026) and showed the largest % weight increase. Conclusions:
Leptin might play a role in neonatal growth trajectories, characterized by an inverse correlation with maternal plasma and milk. PT infants showed the highest correlation with
hormone levels, regardless of source, seeming the most affected group by
leptin guidance. Low
leptin levels appeared to contribute to critical neonates’ ability to recover a correct
body weight at 1 year. An eventual non-physiological “catch-up growth” should be monitored, and
leptin perinatal levels may be an indicative tool. Further investigations are needed to strengthen the results.