Maternal BMI at the time of birth and selected risk factors associated with severe neonatal outcomes: a secondary analysis of the WHO Better Outcomes in Labour Difficulty (BOLD) project

Abstract

The main objective of this secondary analysis was to describe the nutritional status of the Better Outcomes in Labour Difficulty (BOLD) project study population and determine possible associations between maternal nutritional status (as reflected by maternal BMI at the time of birth) and severe neonatal outcomes (SNO). We also analysed previous and index maternal pathologies to determine associations with neonatal outcomes. We used the classification designed by Atalah for maternal BMI and compared with the Hyperglycaemia and Adverse Pregnancy Outcome study one. To describe the nutritional status of this population, figures of distribution and test of normality related to weight and BMI were presented for the women and their babies. To explore the association between maternal BMI data and SNO, the χ2 test was performed. To identify a maternal characteristic or a group of characteristics that could predict SNO, we used Fisher's exact test using previous maternal pathology collected in the BOLD project as well as that in the index pregnancy. In this study, BMI at the time of birth was not associated with neonatal near miss or death. We found that previous maternal obesity, diabetes and chronic hypertension were associated with SNO. Maternal pathology in the index pregnancy such as other obstetric haemorrhage, pre-eclampsia, anaemia and gestational diabetes was associated with SNO.

Keywords: BMI; Maternal BMI; Obesity; Severe neonatal outcomes.