Twin and triplet pregnancy

Resource impact statement

The 2024 guideline update sets out recommendations on progesterone for preventing preterm birth and includes recommendations to offer a cervical length scan in twin and triplet pregnancies.

We expect that the resource impact of this update:

• for any single guideline recommendation in England will be less than £1 million per year (or approximately £1,800 per 100,000 population, based on a population for England of 56.6 million people) and
• for implementing the whole guideline in England will be less than £5 million per year (or approximately £8,800 per 100,000 population, based on a population for England of 56.6 million people).

The recommendation to offer a cervical length scan between 16 and 20 weeks to women or pregnant people with a twin and triplet pregnancy may result in a resource impact at a local level. For maternity units which do not routinely scan twin and triplet pregnancies at present, we expect this update to result in a resource impact for each multiple pregnancy under their care. Depending on local circumstances, this guidance may also require additional training of sonographers so that enough staff members are able to measure cervical length.

It is estimated that approximately 1% of those scanned will be found to have a cervix of 25 mm or less. Treatment for those with a short cervix is with vaginal progesterone which is inexpensive and should not give rise to any additional appointments. However, this treatment should reduce preterm births and the associated neonatal morbidity. Preventing preterm births will lead to cost savings, some of which will be delivered over a long timeframe. This is because being born prematurely can result in lifelong adverse health implications, such as cerebral palsy.

This statement is supported by a resource impact template which may be used to calculate the resource impact of implementing the guideline at a local level.

We understand that there is currently some variation in local practice, with some maternity units already offering a cervical length scan for all multiple pregnancies. Users will need to input the percentage of people scanned for a short cervix in both current and future practice in their locality on the inputs and eligible population worksheet of the template. There is scope within the template to model the savings derived from avoiding adverse maternal outcomes through treating those with a short cervix with progesterone. Users will need to populate the relevant costs on the unit costs worksheet to do this.

Maternity services are commissioned by integrated care boards. Providers are NHS hospital trusts, primary care, and community services.