Smoking status of women at initial assessment, at birth, and who stopped smoking during pregnancy, by local health board
Standard shorthand is used in this table: [x] = not available, [z] = not applicable.
| Data values | Data description | Year | Area | Indicator |
|---|---|---|---|---|
| 21,673 | Number | 2024 | Wales | Records with valid smoking data |
| 20,944 | Number | 2024 | Wales | Records with valid smoking status at initial assessment and birth |
| 2,718 | Number | 2024 | Wales | Records with valid smoking at initial assessment |
| 463 | Number | 2024 | Wales | Records with valid smoking at initial assessment but not at birth |
| 2,890 | Number | 2024 | Wales | Records with invalid smoking data |
| 24,563 | Number | 2024 | Wales | All deliveries |
| 5,153 | Number | 2024 | Betsi Cadwaladr University Local Health Board | Records with valid smoking data |
| 5,110 | Number | 2024 | Betsi Cadwaladr University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 916 | Number | 2024 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment |
| 149 | Number | 2024 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Betsi Cadwaladr University Local Health Board | Records with invalid smoking data |
| 5,153 | Number | 2024 | Betsi Cadwaladr University Local Health Board | All deliveries |
| 175 | Number | 2024 | Powys Teaching Local Health Board | Records with valid smoking data |
| 160 | Number | 2024 | Powys Teaching Local Health Board | Records with valid smoking status at initial assessment and birth |
| 14 | Number | 2024 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment |
| 2 | Number | 2024 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Powys Teaching Local Health Board | Records with invalid smoking data |
| 175 | Number | 2024 | Powys Teaching Local Health Board | All deliveries |
| 2,660 | Number | 2024 | Hywel Dda University Local Health Board | Records with valid smoking data |
| 2,484 | Number | 2024 | Hywel Dda University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 255 | Number | 2024 | Hywel Dda University Local Health Board | Records with valid smoking at initial assessment |
| 0 [z] | Number | 2024 | Hywel Dda University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Hywel Dda University Local Health Board | Records with invalid smoking data |
| 2,660 | Number | 2024 | Hywel Dda University Local Health Board | All deliveries |
| 3,864 | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking data |
| 3,805 | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 540 | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking at initial assessment |
| 153 | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | Records with invalid smoking data |
| 3,864 | Number | 2024 | Cwm Taf Morgannwg University Local Health Board | All deliveries |
| 4,950 | Number | 2024 | Aneurin Bevan University Local Health Board | Records with valid smoking data |
| 4,688 | Number | 2024 | Aneurin Bevan University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 577 | Number | 2024 | Aneurin Bevan University Local Health Board | Records with valid smoking at initial assessment |
| 56 | Number | 2024 | Aneurin Bevan University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Aneurin Bevan University Local Health Board | Records with invalid smoking data |
| 4,950 | Number | 2024 | Aneurin Bevan University Local Health Board | All deliveries |
| 4,871 | Number | 2024 | Cardiff and Vale University Local Health Board | Records with valid smoking data |
| 4,697 | Number | 2024 | Cardiff and Vale University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 416 | Number | 2024 | Cardiff and Vale University Local Health Board | Records with valid smoking at initial assessment |
| 103 | Number | 2024 | Cardiff and Vale University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2024 | Cardiff and Vale University Local Health Board | Records with invalid smoking data |
| 4,871 | Number | 2024 | Cardiff and Vale University Local Health Board | All deliveries |
| 19,817 | Number | 2023 | Wales | Records with valid smoking data |
| 19,220 | Number | 2023 | Wales | Records with valid smoking status at initial assessment and birth |
| 2,738 | Number | 2023 | Wales | Records with valid smoking at initial assessment |
| 536 | Number | 2023 | Wales | Records with valid smoking at initial assessment but not at birth |
| 5,884 | Number | 2023 | Wales | Records with invalid smoking data |
| 25,701 | Number | 2023 | Wales | All deliveries |
| 5,301 | Number | 2023 | Betsi Cadwaladr University Local Health Board | Records with valid smoking data |
| 5,260 | Number | 2023 | Betsi Cadwaladr University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 926 | Number | 2023 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment |
| 112 | Number | 2023 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2023 | Betsi Cadwaladr University Local Health Board | Records with invalid smoking data |
| 5,301 | Number | 2023 | Betsi Cadwaladr University Local Health Board | All deliveries |
| 361 | Number | 2023 | Powys Teaching Local Health Board | Records with valid smoking data |
| 245 | Number | 2023 | Powys Teaching Local Health Board | Records with valid smoking status at initial assessment and birth |
| 26 | Number | 2023 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment |
| 2 | Number | 2023 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2023 | Powys Teaching Local Health Board | Records with invalid smoking data |
| 361 | Number | 2023 | Powys Teaching Local Health Board | All deliveries |
| 0 [x] | Number | 2023 | Hywel Dda University Local Health Board | Records with valid smoking data |
| 0 [x] | Number | 2023 | Hywel Dda University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 0 [x] | Number | 2023 | Hywel Dda University Local Health Board | Records with valid smoking at initial assessment |
| 0 [x] | Number | 2023 | Hywel Dda University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 2,923 [x] | Number | 2023 | Hywel Dda University Local Health Board | Records with invalid smoking data |
| 2,923 [x] | Number | 2023 | Hywel Dda University Local Health Board | All deliveries |
| 4,199 | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking data |
| 4,089 | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 669 | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking at initial assessment |
| 161 | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | Records with invalid smoking data |
| 4,199 | Number | 2023 | Cwm Taf Morgannwg University Local Health Board | All deliveries |
| 5,143 | Number | 2023 | Aneurin Bevan University Local Health Board | Records with valid smoking data |
| 4,963 | Number | 2023 | Aneurin Bevan University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 670 | Number | 2023 | Aneurin Bevan University Local Health Board | Records with valid smoking at initial assessment |
| 171 | Number | 2023 | Aneurin Bevan University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2023 | Aneurin Bevan University Local Health Board | Records with invalid smoking data |
| 5,143 | Number | 2023 | Aneurin Bevan University Local Health Board | All deliveries |
| 4,813 | Number | 2023 | Cardiff and Vale University Local Health Board | Records with valid smoking data |
| 4,663 | Number | 2023 | Cardiff and Vale University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 447 | Number | 2023 | Cardiff and Vale University Local Health Board | Records with valid smoking at initial assessment |
| 90 | Number | 2023 | Cardiff and Vale University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2023 | Cardiff and Vale University Local Health Board | Records with invalid smoking data |
| 4,813 | Number | 2023 | Cardiff and Vale University Local Health Board | All deliveries |
| 20,675 | Number | 2022 | Wales | Records with valid smoking data |
| 18,727 | Number | 2022 | Wales | Records with valid smoking status at initial assessment and birth |
| 2,888 | Number | 2022 | Wales | Records with valid smoking at initial assessment |
| 772 | Number | 2022 | Wales | Records with valid smoking at initial assessment but not at birth |
| 5,890 | Number | 2022 | Wales | Records with invalid smoking data |
| 26,565 | Number | 2022 | Wales | All deliveries |
| 5,590 | Number | 2022 | Betsi Cadwaladr University Local Health Board | Records with valid smoking data |
| 5,537 | Number | 2022 | Betsi Cadwaladr University Local Health Board | Records with valid smoking status at initial assessment and birth |
| 1,012 | Number | 2022 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment |
| 142 | Number | 2022 | Betsi Cadwaladr University Local Health Board | Records with valid smoking at initial assessment but not at birth |
| 0 [z] | Number | 2022 | Betsi Cadwaladr University Local Health Board | Records with invalid smoking data |
| 5,590 | Number | 2022 | Betsi Cadwaladr University Local Health Board | All deliveries |
| 370 | Number | 2022 | Powys Teaching Local Health Board | Records with valid smoking data |
| 272 | Number | 2022 | Powys Teaching Local Health Board | Records with valid smoking status at initial assessment and birth |
| 20 | Number | 2022 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment |
| 6 | Number | 2022 | Powys Teaching Local Health Board | Records with valid smoking at initial assessment but not at birth |
Next update expected:August 2026
Updates
- 20th December 2025
- Dataset first published.
Main information
- Designation
- Accredited official statistics
- Data provider
- Digital Health and Care Wales (DHCW)
- Data source
- Maternity Indicators Dataset (MIDS)
Overview
- Summary of dataset and variables
Number and percentage of women who smoked at initial maternity assessment, at birth and those who stopped smoking during pregnancy, broken down by local health board.
This data is derived from the Maternity Indicators dataset, provided to the Welsh Government by Digital Health and Care Wales (DHCW).
The Maternity Indicators dataset combines records from a mother’s initial assessment with a child’s birth record.
Full details of every data item available in the Maternity Indicators dataset are available through the NHS Wales Data Dictionary.
- Data collection or calculation
Data from the Maternity Indicators dataset only includes initial assessment data where the initial assessment and birth both occurred in the same health board, in Wales only.
Births to Welsh resident mothers who gave birth in England or in any other country outside of Wales are not included in the data.
Data for each calendar year refers to when the baby was born. Initial assessments may have taken place in the previous year but would be counted in the year in which the birth occurred.
Smoking at initial assessment: While there is a high percentage of valid data for smoking status at initial assessment, reliability depends on self-reporting when CO monitoring is unavailable.. CO monitoring was largely suspended during the COVID-19 (2020 to 2023) , so most data in this period is self-reported.
CO monitoring rates:
- Pre-2020: 20–30%
- 2021–2022: 1–2%
- 2024: 28% (near pre-pandemic levels)
E-cigarette use is not detected by CO monitoring and should not be recorded, but some mothers may self-report inaccurately.
Percentages are based on records with valid smoking data; missing data counts are in the quality report.
Smoking at birth: Data faces similar limitations as initial assessment, with increasing missing/invalid records in recent years. At birth, CO monitoring was lower thank at initial assessment:
- 2016–2020: 1–3%
- 2024: 9.8%
The number of records with no stated smoking status at birth can be found in Table 4 of the Maternity and birth statistics quality report tables.
Women who stopped smoking: This analysis is based on women who had valid smoking data at both initial assessment and birth. As smoking status is recorded at two points in time only, the data will not show if mothers were smoking throughout the duration of their pregnancy, or how frequently they smoked. In this analysis, those mothers who were recorded as smoking at initial assessment but not smoking at birth are classed as mothers who ‘stopped smoking’ during pregnancy.
The denominator for the percentage calculation is the total records less records with a ‘not stated’ value at either initial assessment, birth or both.
- Statistical quality
Smoking at initial assessment: Due to data quality issues with the smoking at birth data, smoking at initial assessment for Swansea Bay and Hywel Dda has been excluded from 2021 to 2023 for compatibility purposes.
Smoking at birth: Swansea Bay was not included in the Wales totals from 2021 to 2024 and Hywel Dda was not included in the Wales totals from 2021 to 2023.
In 2024, data for Wales was from the remaining 6 health boards and from 2021 to 2023 was from the 5 remaining health boards. Swansea Bay was excluded from the smoking at birth data due to data quality concerns and Hywel Dda was excluded as they did not provide any data for smoking at birth between 2021 and 2022 and provided incomplete data in 2023. This resulted in excluding smoking at initial assessment for Swansea Bay and Hywel Dda for these time points for compatibility purposes. In 2021 and 2022 Cwm Taf Morgannwg had an unusually high percentage of missing data.
The number of records with missing data has varied throughout the time series and has increased in recent years. The number of missing records can be found in Table 4 of the Maternity and birth statistics quality report tables.
From 1st April 2019 health service provision for residents of Bridgend local authority moved from Abertawe Bro Morgannwg to Cwm Taf. The health board names changed to Cwm Taf Morgannwg University Health Board and Swansea Bay University Health Board. Data for Abertawe Bro Morgannwg and Cwm Taf are available for previous years in this table. More detailed information on the sources of data and analyses in this statistical release are provided in the quality report.
Published by
- Organisation
- Welsh Government
- Contact email
- stats.healthinfo@gov.wales