Neonatal mortality risk of vulnerable newborns: A descriptive analysis of subnational, population‐based birth cohorts for 238 203 live births in low‐ and middle‐income settings from 2000 to 2017
Authors: Hazel Elizabeth A. , Erchick Daniel J. , Katz Joanne , Lee Anne C. C. , Diaz Michael , Wu Lee S. F. , West Keith P. , Shamim Abu Ahmed , Christian Parul , Ali Hasmot , Baqui Abdullah H. , Saha Samir K. , Ahmed Salahuddin , Roy Arunangshu Dutta , Silveira Mariângela F. , Buffarini Romina , Shapiro Roger , Zash Rebecca , Kolsteren Patrick , Lachat Carl , Huybregts Lieven , Roberfroid Dominique , Zhu Zhonghai , Zeng Lingxia , Gebreyesus Seifu H. , Tesfamariam Kokeb , Adu‐Afarwuah Seth , Dewey Kathryn G. , Gyaase Stephaney , Poku‐Asante Kwaku , Boamah Kaali Ellen , Jack Darby , Ravilla Thulasiraj , Tielsch James , Taneja Sunita , Chowdhury Ranadip , Ashorn Per , Maleta Kenneth , Ashorn Ulla , Mangani Charles , Mullany Luke C. , Khatry Subarna K. , Ramokolo Vundli , Zembe‐Mkabile Wanga , Fawzi Wafaie W. , Wang Dongqing , Schmiegelow Christentze , Minja Daniel , Msemo Omari Abdul , Lusingu John P. A. , Smith Emily R. , Masanja Honorati , Mongkolchati Aroonsri , Keentupthai Paniya , Kakuru Abel , Kajubi Richard , Semrau Katherine , Hamer Davidson H. , Manasyan Albert , Pry Jake M. , Chasekwa Bernard , Humphrey Jean , Black Robert E. ,   Subnational Collaborative Group for Vulnerable Newborn Mortality,   Vulnerable Newborn Measurement Core Group
Published: May 2023

Objective

We aimed to understand the mortality risks of vulnerable newborns (defined as preterm and/or born weighing smaller or larger compared to a standard population), in low‐ and middle‐income countries (LMICs).

Design

Descriptive multi‐country, secondary analysis of individual‐level study data of babies born since 2000.

Setting

Sixteen subnational, population‐based studies from nine LMICs in sub‐Saharan Africa, Southern and Eastern Asia, and Latin America.

Population

Live birth neonates.

Methods

We categorically defined five vulnerable newborn types based on size (large‐ or appropriate‐ or small‐for‐gestational age [LGA, AGA, SGA]), and term (T) and preterm (PT): T + LGA, T + SGA, PT + LGA, PT + AGA, and PT + SGA, with T + AGA (reference). A 10‐type definition included low birthweight (LBW) and non‐LBW, and a four‐type definition collapsed AGA/LGA into one category. We performed imputation for missing birthweights in 13 of the studies.

Main Outcome Measures

Median and interquartile ranges by study for the prevalence, mortality rates and relative mortality risks for the four, six and ten type classification.

Results

There were 238 203 live births with known neonatal status. Four of the six types had higher mortality risk: T + SGA (median relative risk [RR] 2.6, interquartile range [IQR] 2.0–2.9), PT + LGA (median RR 7.3, IQR 2.3–10.4), PT + AGA (median RR 6.0, IQR 4.4–13.2) and PT + SGA (median RR 10.4, IQR 8.6–13.9). T + SGA, PT + LGA and PT + AGA babies who were LBW, had higher risk compared with non‐LBW babies.

Conclusions

Small and/or preterm babies in LIMCs have a considerably increased mortality risk compared with babies born at term and larger. This classification system may advance the understanding of the social determinants and biomedical risk factors along with improved treatment that is critical for newborn health.