The effect of the Growth Assessment Protocol (GAP) on stillbirth rates in England
13 April 2021
This research, undertaken by researchers at the Perinatal Institute, used data made available via the Office for National Statistics (ONS) Secure Research Service (SRS), which is being expanded and improved with ADR UK funding.
According to data from ONS, prior to 2012 stillbirth rates in England remained essentially unchanged for about 20 years and were flagged as being amongst the highest in Western Europe. However since 2012 they have continued to fall, year on year.
This research, led by Oliver Hugh at the Perinatal Institute, set to investigate the potential causes and associations for this drop, and the extent to which they related to the implementation of the Growth Assessment Protocol (GAP). This is a programme developed by the Perinatal Institute to improve antenatal detection of fetal growth restriction, the main risk factor for stillbirth.
What they did
The research team analysed a 10-year period from 2008, the year before the first regional roll-out of the GAP program in the NHS, to 2017, in which the latest unit-based ONS data was available.
Assigning births to a number of different variables, including location of NHS Trust, stillbirth rates could be compared pre- and post-implementation of the GAP programme.
Analysis of GAP implementation was based on the Perinatal Institute's own core set of anonymised antenatal and postnatal records.
All 133 maternity units in England were grouped into categories:
- Units that have not implemented GAP
- Units that have implemented GAP partially
- Units with complete implementation of GAP
This analysis has confirmed that the implementation of the GAP programme in the three NHS regions has resulted in significant decline in ONS regional stillbirth rates, while rates in all other regions remained unchanged. Complete implementation of GAP was associated with a significant reduction in stillbirths.
These research findings strengthen the need to maintain a strong focus on fetal growth surveillance, and the need to provide sufficient resources for ultrasound scans. Results will help set priorities within GAP maternity services, and raise the importance of training, audit and benchmarking of performance.
The findings are of relevance for all NHS units, and help explain the causes for the observed improvements while also making it clear that much more can be done. These observations will strengthen the argument for a renewed effort on improving fetal growth surveillance, against the competing priorities and limited resources in the often over-stretched maternity services.
This research won the ONS Research Excellence Awards 2020 - People's Choice Award, voted on by members of the research community, Office for National Statistics, partner organisations and members of the public.