Low birth weight, preterm birth, and small for gestational age combined estimates requiring high quality (individual-level) data
This call requests collaborative sharing of data to address new work on the frequency and outcomes of phenotypes of vulnerable newborns.
Reliable, individual-level data are needed including each newborn having birthweight and gestational age, as well as the relationship to neonatal or infant mortality.
Why take part?
Help us close the global gap for measuring and preventing vulnerability (preterm and low birth weight)
This is a collaborative approach involving governments, academics and also WHO and UNICEF. It will help set jointly agreed priorities to improve data quality and use of data in programmes for vulnerable newborns all over the world.
For centuries, Low Birth Weight (LBW) (<2500g) has been used as the main marker of vulnerability in a newborn. But this is not granular enough to understand the risks and also causes.
LBW is due to one of the following:
- Being born preterm (<37 completed weeks of gestation)
- Growth-restricted (defined as <10th centile of birthweight for gestational age (GA) and sex i.e. small for gestational age (SGA))
- A combination of both
Global estimates of LBW do not discriminate between the babies who had LBW due to prematurity versus those linked to fetal growth restriction.
Population-level data are available for national estimates of LBW from surveys and routine facility data, and to a lesser extent for the prevalence of preterm birth from routine data. However, there are no reliable multi-country data on the various combinations or phenotypes of vulnerable newborns (i.e. prematurity, fetal growth restriction and the combination).
That's what we're hoping to change with your help.
Advantages of working with us:
If you have data that meets criteria to be included in analyses,
- You will be invited to join a collaborative working partnership, and can either analyse the data yourself and provide tables, or provide data for others to analyse.
- You and key members of your team will be invited as collaborative authors on relevant papers.
- Data from each individual study could be also published by your team as a separate paper.
The data criteria
The data should have been collected in year 2000 or later and may be either:
- Nationally representative datasets with cross-linked birth data, in particular gestational age, sex, and birthweight. eg national birth registry
- Large studies (sample size of at least 300 in a given country) of birth cohorts, with high quality gestational age, sex, and birthweight data from countries listed below.
- Data collected from observational studies or in intervention trials are both appropriate.
- Data can be from population-based studies or from hospital births in setting where at least 90% of births occur in hospitals.
Exposure (must have):
Individual-level data on:
- Birth outcome (livebirth or stillbirth),
- Newborn sex
- Gestational age (ideally defined by early pregnancy ultrasound or if other method please note in the table)
- Birth weight (ideally by digital scales and within 24 hrs of birth in a high proportion).
For national datasets we expect a high national coverage of at least 80% of estimated births per year. Both national datasets and birth cohort studies are expected to have at least 80% of births with birthweight data and gestational age recorded.
Outcome measures (desired):
- Stillbirth rate (from 28 weeks GA)
- Neonatal mortality data
Added value if you have data on longer term mortality to age 5 or beyond.
How can you get involved?
- If you think you may have relevant data, please fill the survey with data characteristics by 15th October 2020.
Please contact firstname.lastname@example.org if you have questions. If you do not have all the requested data, we would still like to hear from you if you think the data you have may be relevant
Please share widely to national birth registry/data teams and to research groups with relevant data
Applicable for all countries, high and middle income (more likely national data) and low income (more likely special research datasets)
Fill out the screening survey
- Blencowe H, Cousens S, Oestergaard MZ, C… Lawn JE National, regional, and worldwide estimates of preterm birth rates in the year 2010 with time trends since 1990 for selected countries: a systematic analysis and implications. Lancet (London, England) 2012, 379(9832):2162-2172.
- Chawanpaiboon S, Vogel JP, Moller AB, Lumbiganon P, Petzold M, Hogan D, Landoulsi S, Jampathong N, Kongwattanakul K, Laopaiboon M et al: Global, regional, and national estimates of levels of preterm birth in 2014: a systematic review and modelling analysis. The Lancet Global health 2019, 7(1):e37-e46.
- Blencowe H, Krasevec J, de Onis M, … Lawn JE, Cousens SN National, regional, and worldwide estimates of low birthweight in 2015, with trends from 2000: a systematic analysis. The Lancet Global health 2019, 7(7):e849-e860.