NCARDRS Congenital Condition Official Statistics Report, 2023

As congenital conditions are a large and diverse group of conditions, they are categorised into internationally standardised (EUROCAT) condition groups for reporting. These are broadly defined by the location in the body. Some modifications to these groups and subgroups have been applied and these are described further in the accompanying Technical Details and the Condition group inclusion ICD-10 list. 

Conditions can be grouped into one of 12 major condition groups (e.g., congenital heart disease, nervous system, limb; level 1). These major groups are further divided into condition subgroups (e.g., serious cardiac, NTDs, limb reduction; level 2) and these groups are further divided to produce individual conditions (e.g., Tetralogy of Fallot, spina bifida, longitudinal preaxial limb reduction; level 3), although some degree of aggregation remains in level 3 where conditions are very rare (e.g., the skeletal dysplasias are grouped into one level 3 group). Not every condition has been categorised into a group or subgroup in this data table, although most will be included in one of 12  major condition groups.

The total and live birth prevalence for 115 groups and individual conditions are presented in Data tables 1a to 1c, nationally, by region and by ICB.  

Babies with more than one condition will appear in each applicable row in  Data tables 1a to 1c. More than a third (n= 5,139; 36.5%) of babies diagnosed with congenital conditions had more than one condition in 2023, similar to 2022 (36.9%, n=5,452). 

In addition to grouping by congenital condition, conditions are categorised by the presence or absence of a known genomic association. Conditions known to be genomic include those babies with an identified chromosomal condition, skeletal dysplasia, hereditary skin condition or other genomic conditions.  

The number and proportion of conditions with a known genomic diagnosis (dark blue in Figures 1a and 1b) are likely to be underestimates as these conditions require genomic testing to be offered, accepted and then to deliver a diagnostic result. Additionally, there are known gaps in our dataflows from the NHS Genomic Laboratory Hubs (GLHs). Whilst we have national coverage for traditional cytogenetic testing, data from next generation sequencing (NGS) based tests, including whole genome sequencing, are not yet comprehensive. We continue to work with partners to improve these data flows and incorporate them as they become available. 

Conditions with no known genomic association (light blue in Figures 1a and 1b) are structural conditions in babies where a genomic condition has not yet been identified. This includes babies where a genomic diagnosis was not detected, or where testing was not offered or did not take place. It is important to note that not all babies undergo genomic testing, and it is inevitable that some of the conditions in this category will have an underlying genomic aetiology that has not yet been identified or reported to NCARDRS. These figures are therefore likely to be overestimates.