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Published on: August 25, 2014
Neonatal mortality risk for vulnerable newborn types in 15 countries using 125.5 million nationwide birth outcome
Lorena Suárez-Idueta1, Hannah Blencowe2, Yemisrach B Okwaraji2
1Mexican Society of Public Health, Mexico City, Mexico.
Insights
Preterm newborns, especially those small for gestational age, face the highest mortality risks. Appropriate for gestational age preterm infants contribute most to overall neonatal deaths.
Area of Science:
- Neonatal Health
- Perinatal Epidemiology
- Global Child Health
Background:
- Neonatal mortality remains a significant global health challenge.
- Identifying vulnerable newborn subgroups is crucial for targeted interventions.
- Previous research has not comprehensively compared mortality across diverse vulnerable newborn types.
Purpose of the Study:
- To compare neonatal mortality risks associated with six distinct vulnerable newborn types.
- To analyze the contribution of these types to overall neonatal mortality across 15 countries.
- To investigate the impact of gestational age and size-for-gestational age on neonatal outcomes.
Main Methods:
- Population-based, multi-country study utilizing national data from 15 middle- and high-income countries (2000-2020).
- Analysis of 125.5 million live births, categorizing newborns by gestational age (preterm/term) and size-for-gestational age (small/appropriate/large).
- Calculation of risk ratios (RRs) and population attributable risks (PAR%) for six defined newborn types.
Main Results:
- Highest mortality risks were observed in preterm newborns who were small for gestational age (PT+SGA), preterm appropriate for gestational age (PT+AGA), and preterm large for gestational age (PT+LGA).
- Preterm newborns born before 28 weeks had substantially elevated mortality risks (median RR 279.5).
- Preterm appropriate for gestational age (PT+AGA) newborns were the largest contributors to neonatal mortality at the population level (median PAR% 53.7).
Conclusions:
- Preterm newborn types represent the most vulnerable group, with the highest mortality.
- The combination of preterm birth and small-for-gestational age (PT+SGA) is associated with the most severe mortality risks.
- Due to its higher prevalence, the preterm appropriate for gestational age (PT+AGA) category accounts for the greatest burden of neonatal deaths globally.
Objective:
To compare neonatal mortality associated with six novel vulnerable newborn types in 125.5 million live births across 15 countries, 2000-2020.
Design:
Population-based, multi-country study.
Setting:
National data systems in 15 middle- and high-income countries.
Methods:
We used individual-level data sets identified for the Vulnerable Newborn Measurement Collaboration. We examined the contribution to neonatal mortality of six newborn types combining gestational age (preterm [PT] versus term [T]) and size-for-gestational age (small [SGA], <10th centile, appropriate [AGA], 10th-90th centile or large [LGA], >90th centile) according to INTERGROWTH-21st newborn standards. Newborn babies with PT or SGA were defined as small and T + LGA was considered as large. We calculated risk ratios (RRs) and population attributable risks (PAR%) for the six newborn types.
Main Outcome Measures:
Mortality of six newborn types.
Results:
Of 125.5 million live births analysed, risk ratios were highest among PT + SGA (median 67.2, interquartile range [IQR] 45.6-73.9), PT + AGA (median 34.3, IQR 23.9-37.5) and PT + LGA (median 28.3, IQR 18.4-32.3). At the population level, PT + AGA was the greatest contributor to newborn mortality (median PAR% 53.7, IQR 44.5-54.9). Mortality risk was highest among newborns born before 28 weeks (median RR 279.5, IQR 234.2-388.5) compared with babies born between 37 and 42 completed weeks or with a birthweight less than 1000 g (median RR 282.8, IQR 194.7-342.8) compared with those between 2500 g and 4000 g as a reference group.
Conclusion:
Preterm newborn types were the most vulnerable, and associated with the highest mortality, particularly with co-existence of preterm and SGA. As PT + AGA is more prevalent, it is responsible for the greatest burden of neonatal deaths at population level.
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