Galanin in the amniotic fluid and neonatal birth weight: a prospective observational study

Objective: The aim of the present study was to examine whether an association is present between amniotic fluid (AF) galanin and neonatal birth weight (NBW). Design: Prospective observational study. Setting: Fetal maternal unit in a tertiary teaching hospital. Population: Fifty women of singleton pregnancy who underwent amniocentesis during the second trimester and delivered after the 37th week of gestation. Methods: Amniocentesis 18th-19th gestational week for genetic indication with the use of a 22G needle under real-time sonographic guidance and measurement of galanin concentration in the AF. Main outcome measures: Association between concentration of AF galanin and NBW at term. Results: Galanin was isolated in all samples of AF (median concentration 19.95 pg/mL; range: 19.0-21.7). A strong linear correlation between AF galanin and NBW was detected (tau = 0.928; p<0.001). Non-parametric linear regression analysis revealed that galanin concentration could explain 72.1% of the variance in the NBW, when controlling for gestational week at birth and mother's body mass index at delivery. Conclusions: AF galanin during the second trimester seems to have a strong linear correlation with NBW of term deliveries in singleton pregnancies, even when controlling for important confounders.