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Timing of neonatal mortality and severe morbidity during the postnatal period: a systematic review
Justine Dol1,2, Brianna Hughes2,3, Mercedes Bonet4
1Faculty of Health, Dalhousie University, Halifax, NS, Canada.
Insights
Neonatal mortality is highest in the first week, especially the first day. High-quality postnatal visits are crucial for reducing newborn deaths and severe morbidity.
Area of Science:
- Neonatal Health
- Public Health
- Pediatrics
Background:
- Neonatal mortality and severe morbidity remain significant global health challenges.
- While causes are known, the specific timing of these events in the neonatal period requires further elucidation.
Approach:
- A systematic review and meta-analysis of 51 studies (36 articles) was conducted.
- Data on neonatal mortality and severe morbidity timing were extracted and analyzed.
- Studies reporting daily, weekly, or specific day-range mortality within the first 28 days were included.
Key Points:
- The highest proportion of neonatal deaths occurred on day 1 (38.8%), followed by day 2 (12.3%).
- The first week accounted for 71.7% of all neonatal mortality within the first month.
- Birth asphyxia was the leading cause of death on day 1, severe infection on days 2-7, and diarrhea on days 8-28.
Conclusions:
- Neonatal mortality is concentrated in the first week of life, with a pronounced peak on the first day.
- Timely and high-quality postnatal care, particularly in the initial postnatal week, is essential for mitigating neonatal mortality and severe morbidity.
Objective:
The objective of this review was to determine the timing of overall and cause-specific neonatal mortality and severe morbidity during the postnatal period (1-28 days).
Introduction:
Despite significant focus on improving neonatal outcomes, many newborns continue to die or experience adverse health outcomes. While evidence on neonatal mortality and severe morbidity rates and causes are regularly updated, less is known on the specific timing of when they occur in the neonatal period.
Inclusion Criteria:
This review considered studies that reported on neonatal mortality daily in the first week; weekly in the first month; or day 1, days 2-7, and days 8-28. It also considered studies that reported on timing of severe neonatal morbidity. Studies that reported solely on preterm or high-risk infants were excluded, as these infants require specialized care. Due to the available evidence, mixed samples were included (eg, both preterm and full-term infants), reflecting a neonatal population that may include both low-risk and high-risk infants.
Methods:
MEDLINE, Embase, Web of Science, and CINAHL were searched for published studies on December 20, 2019, and updated on May 10, 2021. Critical appraisal was undertaken by 2 independent reviewers using standardized critical appraisal instruments from JBI. Quantitative data were extracted from included studies independently by 2 reviewers using a study-specific data extraction form. All conflicts were resolved through consensus or discussion with a third reviewer. Where possible, quantitative data were pooled in statistical meta-analysis. Where statistical pooling was not possible, findings were reported narratively.
Results:
A total of 51 studies from 36 articles reported on relevant outcomes. Of the 48 studies that reported on timing of mortality, there were 6,760,731 live births and 47,551 neonatal deaths with timing known. Of the 34 studies that reported daily deaths in the first week, the highest proportion of deaths occurred on the first day (first 24 hours, 38.8%), followed by day 2 (24-48 hours, 12.3%). Considering weekly mortality within the first month (n = 16 studies), the first week had the highest mortality (71.7%). Based on data from 46 studies, the highest proportion of deaths occurred on day 1 (39.5%), followed closely by days 2-7 (36.8%), with the remainder occurring between days 8 and 28 (23.0%). In terms of causes, birth asphyxia accounted for the highest proportion of deaths on day 1 (68.1%), severe infection between days 2 and 7 (48.1%), and diarrhea between days 8 and 28 (62.7%). Due to heterogeneity, neonatal morbidity data were described narratively. The mean critical appraisal score of all studies was 84% (SD = 16%).
Conclusion:
Newborns experience high mortality throughout the entire postnatal period, with the highest mortality rate in the first week, particularly on the first day. Ensuring regular high-quality postnatal visits, particularly within the first week after birth, is paramount to reduce neonatal mortality and severe morbidity.
