Background

Previous estimates have highlighted a large global burden of stillbirths, with an absence of reliable data from regions where most stillbirths occur. The Every Newborn Action Plan (ENAP) targets national stillbirth rates (SBRs) of 12 or fewer stillbirths per 1000 births by 2030. We estimate SBRs and numbers for 195 countries, including trends from 2000 to 2015.

Methods

We collated SBR data meeting prespecified inclusion criteria from national routine or registration systems, nationally representative surveys, and other data sources identified through a systematic review, web-based searches, and consultation with stillbirth experts. We modelled SBR (≥28 weeks' gestation) for 195 countries with restricted maximum likelihood estimation with country-level random effects. Uncertainty ranges were obtained through a bootstrap approach.

Findings

Data from 157 countries (2207 datapoints) met the inclusion criteria, a 90% increase from 2009 estimates. The estimated average global SBR in 2015 was 18·4 per 1000 births, down from 24·7 in 2000 (25·5% reduction). In 2015, an estimated 2·6 million (uncertainty range 2·4–3·0 million) babies were stillborn, giving a 19% decline in numbers since 2000 with the slowest progress in sub-Saharan Africa. 98% of all stillbirths occur in low-income and middle-income countries; 77% in south Asia and sub-Saharan Africa.

Interpretation

Progress in reducing the large worldwide stillbirth burden remains slow and insufficient to meet national targets such as for ENAP. Stillbirths are increasingly being counted at a local level, but countries and the global community must further improve the quality and comparability of data, and ensure that this is more clearly linked to accountability processes including the Sustainable Development Goals.

Funding

Save the Children's Saving Newborn Lives programme to The London School of Hygiene & Tropical Medicine.

WHO first published national, regional, and worldwide estimates of stillbirths in 2011, highlighting the large global burden of stillbirths, with an estimated 2·6 million women and families affected in 2009. ¹ This process also showed the dearth of reliable data in the regions where most stillbirths occur. In 2014, the Every Newborn Action Plan, a global multipartner movement to end preventable maternal and newborn deaths and stillbirths, set a target for national stillbirth rates (SBRs) of 12 or fewer stillbirths per 1000 births in all countries by 2030, accompanied by action in countries to address disparities. ² This stillbirth target was included in response to the requests of many countries during the consultation process. ³ To achieve this target, countries will need to act to reduce preventable stillbirths and improve monitoring of SBRs. ^{4 and 5}

In this study, our objective was to estimate national, regional, and worldwide stillbirth rates and absolute numbers for 195 countries in both 2000 and 2015, to enable an assessment to be made of the extent to which SBRs have changed over time.

We sought to improve on the 2011 WHO exercise and our work previous to that ⁶ in terms of both the quantity of SBR data, by undertaking more extensive searches, and the quality of the data, by applying more stringent inclusion and exclusion criteria. Variation in definitions used for stillbirths affects comparability. For this exercise, we examined the effect of different definitions, and sought to adjust all input SBR data to correspond to a standard definition (≥28 weeks' gestation) before modelling.

We present our methods and results using the Guidelines for Accurate and Transparent Health Estimates Reporting (GATHER) checklist. This is a new reporting checklist for worldwide health estimates that promotes transparency, including the sharing of input data and modelling code . ⁷

For the purposes of these estimates, we defined a stillbirth as a baby born with no signs of life at 28 weeks' gestation or more (third trimester; panel ). When presenting results by region, we used the Millennium Development Goal (MDG) regions ( appendix pp 3–4 ).

Definition of stillbirth

A fetal death or stillbirth is defined as a baby born with no signs of life after a given threshold. For international comparison, WHO defines a stillbirth according to the 10th edition of the International Classification of Diseases (ICD-10) definition of late fetal death. ICD-10, which was developed several decades ago when gestational age assessment was not standard, gives birthweight as the first preference in the definition, with gestational age second. ICD-10 ⁸ defines late fetal death as a death at a birthweight of 1000 g or more, if the birthweight is not available, a gestational age of 28 weeks or more or a length of 35 cm or more. The corresponding values are 500 g, 22 weeks, or 25 cm or more for early fetal death, and 500 g, 22 weeks, or 25 cm or more for miscarriage.

However, the birthweight and gestational age thresholds do not give equivalent results. This problem is compounded by the frequent occurrence of fetal growth restriction, associated with an adverse intrauterine environment before fetal death, and hence a birthweight-based cutoff will give a lower stillbirth rate than one based on gestational age. This difference is most marked the earlier the gestational age: in our new meta-analyses, stillbirth rates across high-income countries were 15% (95% CI 13–17) lower using a 1000 g or more definition compared with 28 weeks or more, whereas stillbirth rates in the USA are 40% lower with the 500 g or more definition compared with 22 weeks or more.

A gestational age threshold would be most appropriate because it is a better predictor of maturity and hence viability than is birthweight, with many fetuses at risk of stillbirth or preterm birth having preceding fetal growth restriction. ⁹ Information about gestational age is also more widely available than for birthweight for many stillbirths, with early ultrasound dating of pregnancies now standard of care in high-income and middle-income countries, and its use is increasing in low-income countries. Hence, most high-income and middle-income national routine data now include robust gestational age data. Even in settings where gestational age is mainly based on last menstrual period, which is less reliable than early ultrasound dating, it is more commonly available than birthweight, especially for those born at home where it is frequently seen as not culturally acceptable to weigh a stillborn baby. ¹⁰

Therefore, we use a 28 week or more definition. Where possible, data were abstracted or requested according to this definition. Data with alternative definitions were adjusted to the 28 week or more definition ( appendix pp 72–75 ).