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Publication, Part of

[MI] Medicines and Pregnancy Registry: Valproate use in females aged 0 to 54 in England (April 2018 to September 2020)


NHS Digital is working in partnership with the Medicines and Healthcare products Regulatory Agency (MHRA) to develop comprehensive national Medicines in Pregnancy Registries which can give a better understanding of the use, benefits, and risks of medicines taken in pregnancy. This report is an analysis of existing administrative patient data as a proof of concept, to establish the use and value of these data sets in supporting robust and sustainable medicine registries. The data produced are designed to support the MHRA in monitoring the level of success of the valproate pregnancy prevention plan and to enable the wider health and care system to further understand outcomes for women prescribed valproate during pregnancy and their children and consequently to improve patient care.

Valproate is a licenced treatment for epilepsy and bipolar disorder. It is associated with a significant risk of birth defects and developmental disorders in children born to women who take valproate during pregnancy. Since its introduction in the UK in 1974, the product information for doctors has included a warning about the possible risk of birth defects. As the nature and magnitude of risks to the unborn childĀ have been increasingly understood, the warnings have been strengthened. Valproate must not be used in any woman or girl able to have children unless she is supported by a Pregnancy Prevention Programme (PPP). This is designed to make sure patients are fully aware of the risks and the need to avoid becoming pregnant.

To monitor the implementation of and adherence to the PPP, understand changes in the use of valproate and the impact of these changes on women and their children, and to facilitate further research into outcomes following the use of valproate in pregnancy, MHRA and NHS Digital initiated development of a valproate registry.

This report is to provide information on the prescribing of medicines in relation to pregnancies based upon data from the core register which has been developed to form the basis of the planned wider medicines registries and to identify limitations in the existing data sources.

The key findings are listed below. 

47,532 females (aged 0 - 54) were prescribed one or more prescriptions for valproate in one or more months within the reporting period

In September 2020:

  • 1,871 (8.5%) were aged 0 to 11 years of age
  • 572 (2.6%) aged 12 to 15 years
  • 8,856 (40.1%) aged 16 to 44 years
  • and 10,799 (48.9%) aged 45 to 54 years

This report finds a general decrease in prescribing prevalence throughout the reporting period

There was a reduction of 5,353 in the number of females who were prescribed valproate in a month:

from 27,448 in April 2018 to 22,095 in September 2020.

New Starters: Fewer females are being prescribed valproate for the first time

Of the 22,095 prescribed valproate in September 2020

195 were not prescribed valproate in the previous 12 months, and therefore classed as new starters. This compares to 241 in September 2019.

Of those females on the register, 462 females had a total of 490 identified conceptions since April 2018

180 females were prescribed valproate in a month in which they were pregnant

Females who had a prescription of valproate in one or more months of their pregnancy.

238 females stopped receiving prescriptions of valproate prior to their pregnancy

238 females were prescribed valproate prior to pregnancy and their last prescription was before they conceived.

Last edited: 28 September 2021 1:57 pm