Created 5 months ago, updated 9 days ago

Modelled estimates of annual live births by year ending date.

Official birth estimates from ONS are considered very accurate, but the lag between the end of the period covered and the publication of estimates is typically 9-12 months. To gain a more timely indication of birth trends, the GLA Demography team produces modelled estimates of annual births based on counts of infants registered with GP practices. Modelled birth estimates can be produced with the same frequency and latency that NHS Digital publishes patient count data - currently this is monthly and with a lag of 1-2weeks.

The approach used to generate the modelled birth estimates was originally described in this 2016 technical note. The methodology relies on the correlation between the count of persons age 0 (i.e. yet to reach their first birthday) on the patient register and resident in an area with the number of births that have taken place in that area over the preceding year. 

The data used to create these modelled birth estimates are:

  1. Modelled estimates of patient counts by age, sex, and local authority of residence
  2. Official estimates of annual live births by local authority of residence

A respository of the code used to generate the modelled birth estimates is available on GitHub at:

The repository's ReadMe provides more information about the methodology used to produce the estimates as well as a summary analysis of their past accuracy.


File combining: official and modelled birth estimates.  Data for English local authority districts, regions, and ITL 2 subregions.

  Other   Region   Local Authority  (130.46 MB)

Selected plots of actual and predicted recent births for English local authorities, regions, and ITL 2 subregions.

Plots are labelled by their geographic code - a csv lookup of codes and names is included in the zip file.

  Region   Greater London   Other   Local Authority

File containing: past birth estimates, modelled counts of patients age 0, actual and modelled ratios of births to patient counts. Data for English local authorities, regions, and ITL2 subregions.

  Local Authority   Region   Other   Greater London