Relationship between paternal excessive weight and neonatal anthropometry in a clinical trial of nutritional counseling for pregnant women with overweight

Background/Objectives Human studies suggest that fathers with obesity influence infant growth and development. This study aimed to evaluate the relationship between paternal body mass index (BMI) and waist circumference (WC) with neonatal anthropometry and adiposity. Methods This study is a cohort nested in a randomized controlled clinical trial of nutritional counseling for pregnant women with overweight. In total, 89 partner-pregnant woman-neonate triads were included. Paternal anthropometric measurements were taken at the time of the interview. Secondary data related to birth were obtained through access to the health information systems. Neonatal skinfold thickness was assessed and the adiposity was estimated using a predictive anthropometric model. Pearson’s correlation and adjusted multivariate linear regression models were employed to evaluate the relationship between paternal BMI and WC with neonatal anthropometric measurements and adiposity. Results In total, 57.0% of the fathers presented a BMI ≥ 25 kg/m² and 14.6% a waist circumference ≥102 cm. The mean ± SD birth weight of the newborns (g) was 3357 ± 538. Paternal BMI and WC were inversely correlated with head circumference at birth [ r = −0.31 ( p = 0.004), r = −0.23 ( p = 0.03), respectively]. Paternal BMI was also inversely correlated with the birth weight standardized by gestational age ( z -score) [ r = −0.23 ( p = 0.03)]. In adjusted multivariate linear regression models, the paternal BMI (kg/m²) was inversely associated with the head circumference at birth (cm) [ β = −0.07 (95% CI −0.15; −0.001) p = 0.04]. Conclusion The data suggest that paternal excessive weight have a negative effect on fetal development, as assessed by anthropometric measurements. The inverse association between paternal BMI and the head circumference at birth was independent of confounders. Future studies with larger sample sizes are necessary to confirm or refute such hypotheses.