Why focus on preterm birth and stillbirth?
Preterm birth and stillbirth: assessing the status and quality of global estimates
Preterm birth burden
Defining preterm birth
Prevalence | Preterm birth as a direct/indirect cause-of-death | Impairment following preterm birth | |||||
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Epidemiological Parameters | Preterm Birth Prevalence Rate | Preterm Birth as Direct Cause of Neonatal Death 2000 | Preterm Birth as Direct Cause of Neonatal Death 2005 | Preterm Birth as Risk Factor for Neonatal Death | Retinopathy of Prematurity | Chronic Lung Disease | Multi-Domain Impairment |
Definition | The proportion of babies born at less than 37 weeks of completed gestation, per 100 live births | Preterm birth direct co006Dplications as the cause-of-death as defined in ICD ie RDS/HMD, necrotizing enterocolitis, intraventricular hemorrhage and other direct complications of preterm birth, or very early neonatal death in newborn of gestational age <32 weeks | Neonatal death in a preterm baby where preterm birth is indirect - for example a baby who is moderately preterm and dies of infection a few days after birth. | A vasoproliferative disorder due to aberrant vascular proliferation of the immature retina. There are 5 stages of severity. The risk of ROP is increased for preterm babies exposed to hyper-oxygenation. | CLD is defined as persistent need for oxygen therapy in order to maintain oxygen saturation above 88% to 36 weeks of postmenstrual age (note some variation in case definitions, also sometimes called Bronchopulonary dysplasia) | Impairment aff ecting more than one domain of function as used in GBD assessments (cognitive, motor, vision, hearing, seizure disorder) | |
Systematic global estimates available (source and date) | WHO and Child Health Epidemiology Reference Group (CHERG) for Global Burden of Disease (GBD), in process | CHERG for WHO/UN [4] | CHERG and WHO in process | CHERG new grant - not yet started | CHERG for GBD, in process | CHERG for GBD, in process (review by Maneesh Batra) | CHERG for GBD, in process |
Countries with VR data used (used as reported, new analysis or adjusted) | Not in vital registration | 45 (~96,797 neonatal deaths) | 61 (~142,000 neonatal deaths) | Work to be done 2009 - 2012 | Not reported consistently from ICD data although ICD codes allocated | Several ICD codes allocated. Not reported consistently from ICD data | Not in vital registration |
Countries with survey data used (used as is, new analysis or adjusted) | Not in current national surveys | Not in current national surveys | Not in current national surveys | Work to be done 2009 - 2014 | Not in current national surveys | Not in current national surveys | Not in current national surveys |
Countries where modelled estimates used (basis of model) | (in process) | 138 (27 from VR model and 111 from study based model) Multinomial model to simultaneously estimate 7 causes. | 132 (32 from VR model and 100 from study-based model). Multinomial model to simultaneously estimate 7 causes. | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Types of data inputs for modelling | (in process) | VR, published studies from community (verbal autopsy) and facilities, unpublished datasets (eg DSS) | VR, published studies from community (verbal autopsy) and facilities, unpublished datasets (eg DSS) | Work to be done 2009 - 2014 | Often hospital registries | Very few comparable studies even in HICs | Varied and no population based studies cohort from LICs identified |
No of studies/ datasets included in global estimate modelling | (in process) | Searches of 6820 hits, 46 studies and 10 unpublished datasets included | Searches of 5591 hits, 71 studies/datasets included | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Total with measure of parameter (e.g., SBs, preterm births) | (in process) | VR (~96,797 neonatal deaths) Study data (13,685 neonatal deaths) | VR (~130,000 neonatal deaths) Study data (23,638 neonatal deaths) | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Median yr of input data | (in process) | VR median year 1999 Study data median year 1991 | VR median year 2004 Study data median year 1991 | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Variability in outcome measurement methods | (in process) | Yes – death certificates/ ICD codes, clinical assess, med records, verbal autopsy | Yes - death certificates/ ICD codes, clinical assess, med records, verbal autopsy | Work to be done 2009 - 2014 | (in process) | varied case definitions | Very varied case definitions, varied age at assessment and multiple assessment tools |
Limitations re population representativeness | (in process) | VR data representative for 46 countries. Study based data often from non representative populations | VR data representative for 69 countries. Study based data often from non- representative populations | Work to be done 2009 - 2014 | Hospital studies and in LIC/MIC from referral centres, few data re moderate gestational age/BWT babies | Hospital studies and only in high income countries | LIC/MIC from referral centers and limited cohort data |
Generalizability to Population of Interest (i.e., geographic match of data to burden) | (in process) | Important gaps in the input data—especially in China, west and central Africa and central Asia | Much improved data for China and India. Still limited for central Africa and central Asia | Work to be done 2009 - 2014 | Limited | Very limited | Very limited |
Is there systematic equity assessment | No | No | No | No | No | No | No |
Global estimate | (in process) | 1.12 million (27.9% of 4 million) | 1.23 million (33.1% of 3.72 million) | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Range | (in process) | 0.74 to 1.38 million | 0.84 to 1.52 million | Work to be done 2009 - 2014 | (in process) | (in process) | (in process) |
Consistency between estimates if more than one set | To compare to WHO global and regional estimates 2009 | First set of systematic estimates | In comparison with 2000 estimates, a reduction in neonatal tetanus deaths, and apparent increase in deaths due to preterm birth | None to compare with | None to compare with | None to compare with | None to compare with |
Overall summary of quality of data input | (in process) | Moderate for high income countries, low for low income countries | Moderate for high income countries, low for low income countries | (in process) | (in process) | (in process) | (in process) |
Overall quality of estimates according to standards for global estimates | (in process) | Moderate to high - transparent methods, advances in multi-cause modelling now the std for multi-cause work but limited by input data and especially consistency in cause-of-death attribution | (in process) | (in process) | (in process) | (in process) | |
Priority areas to improve measurement now | 1. Increase quality and quality of gestational age data in routine data sources 2. Test feasibility/ validity of gestational age data collection through household surveys 3. Test feasibility/ validity of simplified gestational age clinical assessment 4. Increase dissemination of country level best estimates once completed | 1. Disseminate case definition and hierarchies for preterm complications as a direct cause-of-death vs preterm birth as a risk factor, 2. Increase quality and quality of cause-of-death data in vital registration and national audit data 3. Increase quality and quality of SBR data in verbal autopsy data applying and a standard hierarchy 4. Increase dissemination of country level best estimates | Same inputs as required to improve measurement of gestational age and causes of death | 1. Agree on case definitions and measurement tools and ages at which measurement should occur 2. Increase quality and quality of impairment data especially in transitional countries with increasing neonatal survival 3. Disseminate case definitions well so that future studies result in more comparable data, and ideally standard assessment guidelines 4. Advocate for more funding for cohort studies tracking impairment outcomes from preterm birth and other neonatal morbidities |
Preterm birth prevalence rates
Region | Preterm births (x1000) | Preterm birth rate (%) | 95% Confidence Intervals |
---|---|---|---|
World Total | 12,870 | 9.6 | 9.1 - 10.1 |
More developed regions | 1,014 | 7.5 | 7.3 - 7.8 |
Less developed regions | 7,685 | 8.8 | 8.1 - 9.4 |
Least developed regions | 4,171 | 12.5 | 11.7 - 13.3 |
Africa | 4,047 | 11.9 | 11.1 - 12.6 |
Asia | 6,907 | 9.1 | 8.3 - 9.8 |
Europe | 466 | 6.2 | 5.8 - 6.7 |
Latin America & the Caribbean | 933 | 8.1 | 7.5 - 8.8 |
North America | 480 | 10.6 | 10.5 - 10.6 |
Oceania (Australia/New Zealand) | 20 | 6.4 | 6.3 - 6.6 |
Preterm birth rate disparities within countries
Preterm birth prevalence trends
Preterm Births (Percent) | |||
---|---|---|---|
Country | Previously Reported Rates | Recently Reported Rates | Proportionate Change from Previous Rate |
High-Income Countries
| |||
Australia [79] | 5.9 (1994) | 6.6 (2003) | 11.8% |
Canada [19] | 6.3 (1982-1983) | 6.8 (1992-1994) | 7.9% |
Finland [80] | 9.1 (1966) | 5.2 (2001-2005) | -42.8% |
France [81] | 7.9(1972) | 4.0 (1988-1989) | -49.4% |
Israel [82] | 11.5 (1986-1987) | 9.4 (2003-2004) | -18.3% |
Japan [83] | 4.1 (1980) | 5.4 (2000) | 24.4% |
New Zealand [84] | 4.3 (1980) | 5.9 (1994) | 37.2% |
Scotland [85] | 4.9 (1980-1984) | 5.6 (2000-2003) | 14.3% |
United Kingdom | 4.6 (1971-1976) [35] | 6.0 (2002) [86] | 30.4% |
United States [87] | (1990) | (2005) | |
Non-Hispanic white | 8.5 | 11.7 | 37.6% |
Non-Hispanic black (African American) | 18.9 | 18.4 | 2.6% |
Hispanic | 11.0 | 12.1 | 10.0% |
All races | 10.6 | 12.7 | 19.8% |
Sweden [88] | 6.3 (1984) | 5.6 (2001) | -11.1% |
Middle-Income Countries
| |||
Brazil, Pelotas [89] | 11.4 (1993) | 14.7 (2004) | 26.9% |
Brazil, Ribeirão Preto [90] | 8.0 (1978) | 14.8 (1994) | 85.0% |
Brazil, regression based on all studies [38] | 4.0 (1980s) | 12.0 (2000s) | 200.0% |
Chile [91] | 5.6 (1990) | 6.0 (2000) | 7.1% |
China | 7.5 (1981-1982) [35] | 3.5 (1998) [92] | -53.3% |
Indonesia | 18.5 (1983) [35] | 14.2 (1995) [93] | -23.2% |
Uruguay (unpublished data) | 10.1 (1986-93) | 10.3 (2000-2003) | 2.0% |
Latin America database [39] | 9.4 (1985-1990) | 9.5 (1996-2003) | 1.1% |
Low-Income Countries
| |||
Bangladesh | 22.0 (1994-1997 [94] | 16.5 (2000) [95] | -33.3% |
Gambia | 13.5 (1976-1984) [35] | 12.3 (1976-2003) [96] | 0.91% |
Nepal (rural) | 15.8 (1990)- rural 21.8 (1990)-urban [35] | -8.9% | |
Pakistan | 10.2 ([98]1992-94) | 15.7 (2001-02) [99] | 53.9% |
Preterm birth as a cause-of-death, acute morbidity, and disability
Gestational Age (weeks) | Ilesa, Nigeria, 1996-2000 | Pelotas, Brazil, 2004 | Scotland, 1985-1994 |
---|---|---|---|
34-36 | 48 | 15 | 11 |
32-33 | 156 | 61 | 33 |
<32 | 587 | 370 | 194 |
All preterm (<37) | 179 | 66 | 41 |
Preterm morbidity and long-term sequelae
Stillbirth burden
Defining stillbirth
Epidemiological Parameters | Stillbirth Rate Estimates 2000 (SNL/immpact) | Stillbirth Rate Estimates 2000 (WHO) | Stillbirth Rate Estimates 2005 | Intrapartum Stillbirth Rate 2000 | Stillbirth Cause-of-death 2005 |
---|---|---|---|---|---|
Defi nition | For international comparison stillbirth rates refer only to late fetal deaths (>1000g or >28 weeks gest). ICD-10 defines a fetal death as «death prior to the complete expulsion or extraction from its mother of a product of conception, irrespective of the duration of pregnancy; the death is indicated by the fact that after such separation the fetus does not breathe or show any other evidence of life, such as beating of the heart, pulsation of the umbilical cord, or definite movement of voluntary muscles» without specification of the duration of pregnancy. The denominator is all live births plus late fetal deaths. | Stillbirths in the last trimester (late fetal deaths) occurring during the time of labour, but excluding major congenital abnormalities. In verbal autopsy data «fresh stillbirth» is used as a surrogate marker for intrapartum stillbirth. The denominator is all live births plus late fetal deaths. | Multiple classification systems are in use. A comparable system to map the results of verbal autopsy data on cause-of-death with more complex classification systems is urgently needed. | ||
Systematic global estimates available? Source and date | Stanton, Lawn et al, Lancet 2006 | WHO MPS, 2006 | GAPPS, GBD, CHERG, WHO (Stanton, Lawn et al in process) | Lawn, Shibuya, Stein WHO Bull, 2005 | GAPPS, GBD, CHERG, WHO (Stanton, Lawn et al in process) |
N of countries with VR data used (note if used as reported, new analysis or adjusted) | 44 countries with adult VR coverage > 90%; rates adjusted by model coefficient for VR to allow for under reporting | 102 countries with SBR data used as reported; | 33 VR (plus 11 from EuroPeristat, some of which are VR-based) | Not in Vital registration | Not in vital registration |
N of countries with survey-based estimate used (note if used as is, new analysis or adjusted) | 1 country, adjusted by model coefficient | 102 countries with SBR data used as reported; | In process - | Not in current national surveys | Only 1 national surveys with SB COD data |
N of countries where model-based estimate is used (basis of model) | Model-based estimates are used for 128 countries; based on a random eff ects model | 88 countries - based on average SBR:ENMR ratio for that region | (in process) | 52 countries with data, 141 countries with estimate based unadjusted reported data by country or if no country data on median for WHO subregion (14 subregions) | (in process) |
Types of data inputs used in the model | VR, published studies from community and facility-based studies, household surveys, unpublished datasets | Historical data from 12 High Income Countries were used to calculate a ratio of SBR:ENMR, and was applied to generate SBR from ENNMR for high mortality settings | VR, published data from community and facility-based studies, household surveys, unpublished datasets | National registries, published data from community and facility-based studies, unpublished datasets | National registries, published studies from community and facilities, unpublished datasets |
N of observations included in estimation dataset | 323 observations resulting from searches of 33,714 citations, plus household surveys and additional unpublished datasets | 102 country estimates, plus historical trend data from 12 developed countries | 437 observations | 73 observations resulting from searches of 13,496 citations | ~70 datasets |
Median year of input data | Median year for High Income Countries = 1998; Median year for Low Income Countries = 1990 | Acceptable date range not specifi ed | 2000 | 1995 | 2000 (range 1981-2008) |
Variability in outcome measurement methods | Yes | Yes | Yes | Yes | Yes, includes clinical assessment; medical records, ICD codes, Verbal Autopsy results |
Limitations re: population representativeness | Yes; ~20% of observations from sub-Saharan Africa and South Asia rely on data from hospital studies (likely biased) | No, all observations used were national in scope | Yes; ~41% of observations from both sub-Saharan Africa and S/ SE Asia rely on data from hospital studies (likely biased) | Study based data often from non representative populations | Yes, ~68% of low income country obs from hospital data |
Generalizability to population of interest (ie., match between burden of disease and geographic distribution of data ) | 73% of observations in dataset from Low Income Countries; 24% from sub-Saharan Africa; 21% from SE and S Asia | 47 Low Income Countries had estimates based on the 1.2 SBR:ENMR ratio from historical High Income Countries | 56% of observations from high income countries | Important gaps in the input data, especially: China, central Africa and central Asia | ~40% of observations from low income countries |
Is there systematic equity assessment | No | No | No | No | No |
Global estimate | SBRate = 24 per 1000 births N of stillbirths = 3.2 million | SBRate =24 per 1000 births N of stillbirths = 3.3 million | (in process) | 1.02 million | (in process) |
Range | Range of SBRates: 19 – 30 per 1000 Range of N’s of stillbirths: 2.5 - 4.1 million | Wide uncertainty assumed, but not quantified | (in process) | 0.66 million - 1.48 million | (in process) |
Consistency between estimates if more than one series | Good consistency at global, reasonable at regional but poor at country level | to compare when done | none to compare with | none to compare with | |
Overall summary of quality of data input | Moderate for High Income Countries, low for Low Income Countries | Moderate/low for High Income Countries, very low for Low Income Countries | Moderate/low for High Income Countries, very low for Low Income Countries | ||
Overall summary of estimates Quality according to standards for global estimates | Moderate - transparent methods but limited by input data and by adjustments made to 18 countries which increases global total of stillbirths by approximately 1 million | Moderate to Poor - limited by input data, not fully transparent inputs, the output for high mortality settings is dependent on ENMR (some of which are model-based) and multiplying all the ENMRs by 1.2, which increases the global total of stillbirths by approximately 1 million ; | Moderate - limited by input data and median-based method which may be less sensitive than results from a regression-based model | ||
Priority areas to improve measurement now | 1. Increase consistency in use of definitions (weight/gest age cut-off s) 2. Increase quantity and quality of SBR data in vital registration and national audit data 3. Increase quantity and quality of SBR data from household surveys 4. Increase dissemination of country level best estimates of SBRs | 1. Agree on a simple, consistent classifi cation system 2. Increase quantity and quality of stillbirth time and cause-of-death data in vital registration and national audit data 3. Increase quantity and quality of SBR data from verbal autopsies 4. Increase dissemination of country level best estimates of SB time and cause-of-death |
Stillbirth rates estimates
Stillbirth Rate per 1,000 births | ||
---|---|---|
World Region (WHO regions) | WHO estimate | SNL/immpact estimate (95% CI) |
World | 24 | 23.9 (18.8-30.5) |
HICs | 4 | 5.3 ( 4.2- 6.8) |
LMICs | 26 | 25.5 (20.0- 32.5) |
North Africa | 16 | 18.6 (14.1-24.7) |
Sub-Saharan Africa | 34 | 32.2 (25.4-40.9) |
Latin America/Caribbean | 10 | 13.2 (10.4-16.7) |
East Asia | 19 | 23.2 (18.3-29.5) |
South Asia | 34 | 31.9 (25.0-40.7) |
Southeast Asia | 18 | 12.7 (10.0-16.0) |
West Asia | 16 | 18.9 (14.3-24.9) |
Eurasia | 23 | 12.2 ( 9.5-15.5) |
Oceania | 17 | 15.8 (12.4- 20.1) |
Availability of stillbirth rate data
Stillbirth causes of death
Opportunities to improve data on preterm births and stillbirths
Preterm birth data improvement
Improving measurement of preterm birth prevalence
Opportunities Immediately Available | |||
---|---|---|---|
Opportunities | High-Income Settings | Low-Income Settings | Research Priorities (Focus on high mortality, low quality data settings) |
Comparable case definitions and better definitions of phenotypes | Use 37 completed weeks of gestation but also advance data for very preterm (<34 weeks) and moderate (34-36.9) as well as for spontaneous and medically induced preterm birth | Prioritize improved collection of representative population-based data preterm prevalence as a key starting point | Development of simple and feasible proxy indicators for gestational age (e.g., weight) |
Mechanisms for data collection | Include gestational age and birth weight data on birth certificates and perinatal death certificates. Cross-link data from vital registration and health facility surveillance. | Improve vital registration systems. Use specific death certificates for stillbirths/neonatal deaths and include gestational age and birth weight data on birth certificates | Validation of approaches to assess gestational age through household survey data |
Cause-of-death attribution mechanisms | Use vital registration specific death certificates for stillbirth and neonatal deaths. Revise current ICD codes for preterm birth to reflect change in focus from birth weight to gestational age | In large-scale surveys, follow-up interviews with a verbal autopsy for recent stillbirth and neonatal deaths. Use standardized verbal autopsy tool, case definitions and hierarchical attribution for cause-of-death. Provide clear guidelines for when to attribute death to preterm complications. | Evaluation of the use and reliability of a standardized verbal autopsy tool, case definitions and hierarchy of causes of death. Development of verbal autopsy classification software which provides greater consistency and costs less than expert assessment of verbal autopsy data |
Counting avoidable factors, using data in programmes | Increase the number of national audit systems Consider confidential enquiry for neonatal deaths and stillbirths, as well as maternal deaths | Develop or modify audit systems linking maternal/fetal and neonatal deaths. Compile national data and/or promote sentinel sites in varying health system contexts to ensure that the information is useful for policy prioritization, even if not representative of the population. Consider focusing on few indicators initially (e.g. Intrapartum Case Fatality Rate). Use existing data (e.g., facility birth registers) for local monitoring and programmatic decision-making. | Evaluation of simple audit tools and a mechanism to maximize resultant change in policy and programs. |
Option 1: Birth weight as a surrogate measure
World Region (UNICEF) | Percent of Births NOT Weighed at Birth |
---|---|
South Asia | 74 |
Sub-Saharan Africa | 65 |
Middle East and North Africa | 60 |
East Asia and Pacific | 30 |
CEE/CIS | 21 |
Latin America and Caribbean | 17 |
Birth Weight (Grams) | Uruguay 1986-2003 (n=476,571) | Pelotas 1982, 1993, 2004 (n=14,117) |
---|---|---|
3,000+ | 3.0% | 3.4% |
2,500-2,999 | 14.6% | 13.4% |
2,000-2,499 | 49.0% | 45.0% |
1,500-1,999 | 84.8% | 88.7% |
<1,500 | 93.4% | 97.5% |
All | 10.7% | 11.0% |
Option 2: Clinical assessment of gestational age
Improving measurement of other parameters related to the burden of preterm birth
Stillbirth data improvement
Improving the data on stillbirth rates and numbers
Opportunities Immediately Available | |||
---|---|---|---|
Opportunities | High-Income Settings | Low-Income Settings | Research Priorities (Focus on high mortality, low quality data settings) |
Comparable case definitions for stillbirth | Use 28 week cut-off for international comparisons and 22 week cut-off for High-Income Country comparisons. Local definitions can be used for local purposes. | Prioritize improved collection of representative population-based data for last trimester and intrapartum stillbirths. | Development of simple and feasible proxy indicators for gestational age (e.g., weight) |
Mechanisms for counting all births, (including stillbirths) | Improve vital registration data by establishing specific death certificates for stillbirth and neonatal deaths. Cross-link data from vital registration and health facility surveillance. | Increase attention to training and field supervision for DHS-type household surveys which rely on retrospective reporting of all births. Consider adding stillbirth data collection to MICS surveys. Analyze existing pregnancy loss data from sentinel surveillance sites and increase the number of sentinel surveillance sites which prospectively collect stillbirth data. Improve vital registration systems and register stillbirths. Use specific death certificates for stillbirths/neonatal deaths. | Validation of existing approaches for pregnancy loss data collection compared to pregnancy loss data from sentinel surveillance sites |
Classification for stillbirth cause-of-death | Obtain consensus on a single classification system with a limited number of programmatically relevant, comparable categories, that can be distinguished in low income settings through verbal autopsy, but can also be directly incorporated into more detailed sub groups necessary in high income settings | Evaluation of validity and feasibility of a simple standard classification system for stillbirth cause-of-death | |
Cause-of-death attribution mechanisms | Use vital registration specific death certificates for stillbirth and neonatal deaths. Revise current ICD codes for stillbirths to reflect changes in attribution of cause-of-death since the 1980s. | In large-scale surveys, follow-up interviews with a verbal autopsy for recent stillbirth and neonatal deaths. Use standardized verbal autopsy tool, case definitions and hierarchical attribution for cause-of-death. | Evaluation of the use and reliability of a standardized verbal autopsy tool, case definitions and hierarchy of causes of death. Development of verbal autopsy classification software which provides greater consistency and costs less than expert assessment of verbal autopsy data |
Counting avoidable factors, using data in programmes | Increase the number of national audit systems .Consider confidential enquiry. | Develop or modify audit systems linking maternal/fetal and neonatal deaths. Compile national data and/or promote sentinel sites in varying health system contexts to ensure that the information is useful for policy prioritization, even if not representative of the population. Consider focusing on few indicators initially (e.g. Intrapartum Case Fatality Rate). Use existing data (e.g., facility birth registers) for local monitoring and programmatic decision-making. | Evaluation of simple audit tools and a mechanism to maximize resultant change in policy and programs. |
Option 1 - Vital registration
Option 2 - Population-based surveys
Option 3 - Demographic surveillance sites and special research studies
Improving stillbirth cause-of-death data
Conclusion
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Systematic estimates for causes of stillbirth are required to increase visibility and prioritize action to reduce these deaths. Agreement around a simplified classification system is a key step to underpin global estimates.
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The lack of systematic country-level estimates for the prevalence of preterm birth, based on well-defined and standard phenotype classification, is an important gap affecting the visibility of preterm birth globally. The lack of information for preterm prevalence is most marked in Africa and the Eastern Mediterranean. Virtually no consistent data on preterm prevalence trends are available from LMICs. The development of methods to permit reliable population-based data on trends in preterm birth in these countries is a key priority.
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New analysis is required to better define the risk of death at varying gestational ages, and to separate direct from indirect risks. Input data sets would need to include individual-level data on birth weight, gestational age, mortality outcome, and ideally, comparable causes of death.
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Acute morbidity and long-term sequelae of preterm birth remain virtually unstudied in LMICs, despite the fact that survival is now increasing in some of these settings. Tracking morbidity is crucial. Standard tools and protocols to assess morbidity and long-term sequelae across varying cultures are lacking. Attempts at these global estimates are severely hampered by the lack of data.
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Improve the capture and quality of pregnancy outcome data through household surveys, which is the main data source for the countries with 75% of the global burden, and undertake validation studies. The expanded number of demographic surveillance sites currently functioning in various LMICs offer excellent opportunities to compare prospective versus retrospective reporting on pregnancy outcomes.
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Increase awareness of, and compliance with, standard definitions for stillbirth and preterm birth, and more frequently include stillbirth and gestational age data in existing data collection systems (vital registration, facility-based data and research studies). Current ICD 10 codes for both stillbirth and preterm birth need to be updated to reflect definitions currently in use and advances in understanding made in the last decade. A simplified classification system for stillbirth cause-of- death could also be incorporated into the ICD 11. This would allow data from a standardized verbal autopsy tool and other data collection systems in LMICs to improve input data for future global estimates.
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Expand and strengthen the coverage and quality of existing data collection mechanisms, especially vital registration, and facility data by instituting a standard death certificate for stillbirth and neonatal death linked to revised International Classification of Diseases coding.
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Validate a simple, standardized classification system for stillbirth cause-of-death that is feasible though verbal autopsy.
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Improve systems and tools to capture acute morbidity and long-term impairment outcomes following preterm birth and other adverse pregnancy or neonatal events.