An Analytical Study of Short-Term Morbidities in Large for Gestational Age Infants- A Single Centre Experience from South India

Abstract

Introduction: Globally, Large for Gestational Age (LGA) infants constitute a significant proportion of live births, with Gestational Diabetes Mellitus (GDM) being a primary contributor. Infants born to GDM mothers are more prone for morbidity and mortality and if born large, the incidence of morbidities could increase. The clinico-demographical profile of LGA infants has not been well analysed, especially in Lower Middle Income Countries (LMIC) like India, where gestational diabetes is very common. Aim: To analyse the incidence, demographic profile and short-term neonatal outcomes of LGA births, stratified for GDM. Materials and Methods: This was an analytical retrospective cohort study conducted in a tertiary care hospital in South India. Medical records of LGA infants ≥35 weeks born between December 2018 and May 2020 were reviewed (in December 2020 and January 2021), after Institutional Human Ethics committee approval (No:296/IHEC/JAN 2021). The LGA infants were grouped as GDM induced large infants born to gestational and pregestational diabetes mellitus mothers (LIDM) and large infants born to non-gestational diabetes mellitus mothers (LnIDM). Case records with incomplete data were excluded. Demographic profile of the two groups at birth and their clinical morbidities during hospitalisation were recorded. The primary outcome was requirement of respiratory support in the two groups. The categorical outcomes were compared using Chi-square test/Fisher's exact test, while numerical variables were compared using Mann-Whitney U test. Odds ratio and their 95% Confidence Intervals (CI) were obtained as appropriate. Multivariate logistic regression, controlling for potential confounders, was done to derive the adjusted odds ratio. The p-value <0.05 was taken as significant. All analysis was performed using Statistical Package for the Social Sciences (SPSS) software version 22.0. Results: Out of 2653 live births, 268 were LGA infants ≥35 weeks (9.72%). LIDM were 126 (48.8%) and LnIDM were 132 (51.2%). Ten case records were excluded due to incomplete data hence, 258 infants were included in the final analysis. The median (Interquartile range) birth weight was significantly higher in the LIDM’s {3.92(3.86, 4.08) kg} compared to LnIDM’s {3.89(3.75, 3.96) kg}. The primary outcome of need for respiratory support was not significantly different between the two groups (aOR 1.62; 95% CI 0.92 -2.83; p-value=0.08). Multivariate logistic regression, controlling for confounders, showed higher neonatal intensive care admission rates (aOR 2.15; 95% CI 1.17-4, p=0.01), neonatal hyperbilirubinemia (aOR 1.70; 95% CI: 1.01-2.84, p=0.04) and Persistent Pulmonary Hypertension (PPHN) (aOR 4.43; 95% CI: 1.41-13.82, p=0.004) in the LIDM infants. Conclusion: GDM contributes significantly to LGA births in India, and is associated with higher NICU admissions, neonatal hyperbilirubinemia and PPHN, compared to non-GDM causes.