Elsevier

The Lancet

Volume 377, Issue 9774, 16–22 April 2011, Pages 1319-1330
The Lancet

Articles
National, regional, and worldwide estimates of stillbirth rates in 2009 with trends since 1995: a systematic analysis

https://doi.org/10.1016/S0140-6736(10)62310-0Get rights and content

Summary

Background

Stillbirths do not count in routine worldwide data-collating systems or for the Millennium Development Goals. Two sets of national stillbirth estimates for 2000 produced similar worldwide totals of 3·2 million and 3·3 million, but rates differed substantially for some countries. We aimed to develop more reliable estimates and a time series from 1995 for 193 countries, by increasing input data, using recent data, and applying improved modelling approaches.

Methods

For international comparison, stillbirth is defined as fetal death in the third trimester (≥1000 g birthweight or ≥28 completed weeks of gestation). Several sources of stillbirth data were identified and assessed against prespecified inclusion criteria: vital registration data; nationally representative surveys; and published studies identified through systematic literature searches, unpublished studies, and national data identified through a WHO country consultation process. For 2009, reported rates were used for 33 countries and model-based estimates for 160 countries. A regression model of log stillbirth rate was developed and used to predict national stillbirth rates from 1995 to 2009. Uncertainty ranges were obtained with a bootstrap approach. The final model included log(neonatal mortality rate) (cubic spline), log(low birthweight rate) (cubic spline), log(gross national income purchasing power parity) (cubic spline), region, type of data source, and definition of stillbirth.

Findings

Vital registration data from 79 countries, 69 nationally representative surveys from 39 countries, and 113 studies from 42 countries met inclusion criteria. The estimated number of global stillbirths was 2·64 million (uncertainty range 2·14 million to 3·82 million) in 2009 compared with 3·03 million (uncertainty range 2·37 million to 4·19 million) in 1995. Worldwide stillbirth rate has declined by 14·5%, from 22·1 stillbirths per 1000 births in 1995 to 18·9 stillbirths per 1000 births in 2009. In 2009, 76·2% of stillbirths occurred in south Asia and sub-Saharan Africa.

Interpretation

This study draws attention to the dearth of reliable data in regions where most stillbirths occur. The estimated trend in stillbirth rate reduction is slower than that for maternal mortality and lags behind the increasing progress in reducing deaths in children younger than 5 years. Improved data and improved use of data are crucial to ensure that stillbirths count in global and national policy.

Funding

The Bill & Melinda Gates Foundation through the Global Alliance to Prevent Prematurity and Stillbirth, Saving Newborn Lives/Save the Children, and the International Stillbirth Alliance. The Department of Reproductive Health and Research, WHO, through the UN Development Programme, UN Population Fund, WHO, and World Bank Special Programme of Research, Development and Research Training in Human Reproduction.

Introduction

In 2006, two sets of stillbirth rate estimates for 2000 were published—one by WHO1 and one by the Saving Newborn Lives/Initiative for Maternal Mortality Programme Assessment (IMMPACT).2 These reports were the first published national estimates of stillbirth rates. Both generated similar worldwide totals—3·3 million1 and 3·2 million2 stillbirths in 2000—and, in some cases, similar regional totals. These worldwide estimates are similar to the worldwide total of early neonatal deaths in 2000 (3·0 million) and are higher than the yearly total of deaths from HIV/AIDS in 2004 (1·8 million).3 Despite the similarities between the two reports, the estimated country-specific rates differed substantially for several countries, with differences of a factor of two to three for some countries (figure 1).

We use the WHO-agreed definition of stillbirth for international comparison (≥1000 g birthweight or ≥28 completed weeks of gestation).1, 4, 5 We identified several areas that need attention to develop the previous work and to take into account recent advances and debates on worldwide estimates.6 We sought to broaden and update the input data, particularly from low-income countries, and to use the neonatal mortality rate rather than the infant mortality rate as a model predictor, because the neonatal mortality rate is more closely associated with factors affecting stillbirth (eg, care during pregnancy and around the time of birth). Both the WHO1 and Saving Newborn Lives/IMMPACT2 stillbirth estimates had difficulties with generation of plausible estimates for high-mortality countries, partly because of the scarce availability of data of reasonable quality from sub-Saharan Africa and Asia. In response to this difficulty, both groups made post-modelling adjustments to their estimates for several countries. We estimate that these adjustments resulted in increases in the estimated number of worldwide stillbirths of 565 000 (WHO)1 and 670 000 (Saving Newborn Lives/IMMPACT),2 which is equivalent to increases of 17% and 21%, respectively, in the worldwide number of stillbirths. In this new exercise undertaken jointly with WHO, we aimed to avoid such adjustments to the estimates.

In this Article, we estimate national, regional, and worldwide stillbirth rates and numbers for 193 countries in 2009, retrospectively estimating to 1995 using the same model, and we provide a quantitative assessment of the uncertainty of these estimates. We also present detailed individual-country rates for 2008 for ease of comparison with existing data on neonatal and maternal mortality rates.

Section snippets

Data inputs

The input dataset was compiled from three sources. First, data from countries with vital registration systems that report stillbirths, or with specific perinatal mortality reporting systems, were identified; if the data were available, these were accessed and assessed for inclusion. We accessed data from national stillbirth registries, including Euro-Peristat and national statistical websites.7, 8, 9, 10, 11, 12 Additionally, the International Stillbirth Alliance requested data based on the

Results

The final dataset used (figure 2) comprised 1149 datapoints for stillbirth rate, after exclusion of 39 datapoints as implausible outliers (37 with a stillbirth rate to neonatal mortality rate ratio of <0·25, and two with a stillbirth rate to neonatal mortality rate ratio of >4·0). 527 datapoints (45·9%), with a median reference year of 2002 were from countries in regions of low neonatal mortality; 467 datapoints (40·6%; 2002) were from countries in regions of moderate neonatal mortality; and

Discussion

We estimated yearly national stillbirth rates and numbers from 1995 to 2009. The estimated number of global stillbirths was 2·64 million in 2009 compared with 3·03 million in 1995. In view of the expanded and updated input data, especially with a systematic country consultation and improved modelling, including avoidance of post-modelling adjustments in countries with high stillbirth mortality rates, these results provide more accurate and updated data than do the two previous studies to

References (35)

  • Global health estimates

  • Perinatal mortality 2008. London: Centre for Maternal and Child Enquiries

  • The national board of health and welfare, Sweden

  • Nés vivants et enfants sans vie selon la situation matrimoniale des parents, France 1994–2009

  • Das Informationssystem der Gesundheitsberichterstattung des Bundes, Germany

  • National perinatal statistics unit, Australia

  • Statistics Canada, Canada

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