Leptin levels in breast milk of mother bearing girls and boys

Clinical studies indicate that females have higher blood leptin levels when compared with
the male gender, however to date there is no available report on the impact of offspring gender on maternal
milk leptin (ML) levels. Therefore, this study was designed to investigate the effect of child gender on ML
levels.
Materials and Methods: A cross-sectional study was carried out across Urmia city health centers, Iran.
115 mothers were selected across a wide range of population. A questioner was designed with respect to
infant gender, age and weight. Questioners were filled by all applicants and a
10 ml breast milk sample was taken for further analysis of ML levels and specific gravity (SG)
determination. Mothers were divided into 5 different groups based on offspring's age.
Results: Maternal ML levels were significantly different according to offspring gender. ML levels were
significantly higher in mothers with girls than mothers who have given birth to baby boy. However, there
was no significant difference between ML levels with respect to infant age. SG level was found to be
different among all groups and no significant correlation was found between SG and ML levels of all
applicants.
Conclusion: It was concluded that maternal ML levels varies with respect to the offspring gender. ML
levels in infant girls are higher than that of the boy; however the mechanism of action is still unclear. A
normal reduction in salt and water retention that occurred postpartum may cause slight elevation in SG of
the breast milk.