Maternal gestational weight gain and the long-term physical and neurological outcome of small for gestational age children: A 4-year real-world study based on a longitudinal cohort

Background: Globally, small for gestational age (SGA) is increasingly prevalent, paralleling the common high-risk pregnancies with inappropriate gestational weight gain (GWG). However, whether maternal GWG was associated with their SGA offspring's long-term development remained unresolved.

Objective: To examine the associations of maternal GWG with the long-term physical and neurological development of SGA children based on a real-world cohort in our hospital.

Study design: This retrospective cohort was conducted at our hospital between July 1, 2020, and December 2022. At baseline, we included 319 children diagnosed as SGA and followed up with these children for 12 to 48 months (median: 29 months). The primary outcomes were children's physical and neurological development at follow-ups which were grouped into those with inadequate, adequate, or excessive maternal GWG. We standardized the weight, height (length), body mass index, and ASQ-3 / ASQ:SE domain scores of children with different ages and genders into Z-scores to increase comparability. The adjusted odds ratio (OR) and its 95 % confidence interval (CI) controlling for covariates were calculated using the Hosmer-Lemeshow test model to assess the risk of impaired neurodevelopment.

Results: Firstly, the birth weight and birth length of newborns in the inadequate GWG group were both smaller than those in the adequate GWG group and excessive GWG group. The proportions of severe SGA, neonatal respiratory distress syndrome, and bronchopulmonary dysplasia were higher in the inadequate GWG group compared to the adequate GWG group. Secondly, follow-up observations found that inadequate GWG group had significantly lower weight Z scores(0.12 vs 0.34), height Z scores(-0.11 vs 0.32)and high emaciation incidence (14.3 % vs. 5.0 %) compared to the adequate GWG group. Thirdly, in the follow-up of the neurodevelopment, children in the adequate GWG group had statistically higher Z scores in the gross motor, fine motor, problem-solving and personal-social domains compared to those in the inadequate GWG group and had statistically higher Z scores in the gross motor domain compared to those in the excessive GWG group; children in the excessive GWG group had statistically higher Z scores in the fine motor and personal-social domains compared to those in the inadequate GWG group. Inadequate GWG group was significantly correlated with a higher risk of delayed development in gross motor (OR 1.79, 95 % CI 1.15-2.77), fine motor (OR 1.6, 95 % CI 1.06-2.78), problem-solving (OR 2.08, 95 % CI 1.16-3.56), personal-social (OR 1.51, 95 % CI 1.05-2.18), and social-emotional (ASQ:SE) (OR 1.84, 95 % CI 1.05-3.22) domains than adequate GWG group. Meanwhile, excessive GWG group was significantly correlated with a higher risk of delayed development in gross motor (OR 1.6, 95 % CI 1.02-2.48) domain than adequate GWG group.

Conclusion: Inappropriate maternal GWG (inadequate or excessive) may affect the long-term physical and neurological development of SGA infants. Pregnant women, especially those with intrauterine growth restriction, need to maintain reasonable GWG and receive close monitoring and timely interventions to improve SGA children' long-term outcomes.