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Publication, Part of

[MI] Medicines and Pregnancy Registry - Antiepileptic use in females aged 0 to 54 in England: April 2018 to September 2021


NHS Digital is working in partnership with the Medicines and Healthcare products Regulatory Agency (MHRA) to develop comprehensive national Medicines and 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 (PPP) 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.

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

This publication introduces an interactive dashboard for the presentation of the data.


Antiepileptics are important in controlling seizures and other epilepsy symptoms and untreated epilepsy in pregnancy can result in harm to the mother and child. However, use of some antiepileptic drugs during pregnancy has been associated with a range of harmful effects to the child. Valproate is a licensed 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. In 2018, following further evidence on the nature and magnitude of risks to the unborn child the MHRA advised that 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.

In January 2021, the Commission on Human Medicine (CHM) published a review of the available safety data for antiepileptics during pregnancy. Their report concluded that data show that carbamazepine, phenobarbital, phenytoin, and topiramate are associated with an increased risk of major congenital malformations although data on the risk with some of these other antiepileptics are limited. They also highlighted data for topiramate, phenobarbital, and phenytoin that raises concerns that use of these products during pregnancy may be associated with poorer development outcomes in children, although available studies are limited for these as they are for other antiepileptics with regards to this risk. The report concluded that lamotrigine and levetiracetam are the safer antiepileptics to use during pregnancy. However, even for these medicines, data are not available to rule out a risk of neurodevelopmental disorders and delays.

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.


It is important women do not stop taking their antiepileptic medicine without first discussing it with their doctor. Women receiving treatment who anticipate they may become pregnant at any point in the future are advised to discuss their treatment with a healthcare professional.

Key Facts

49,599 females (aged 0 - 54) were prescribed valproate on one or more occasion between April 2018 and September 2021

Of which, 20,192 females were prescribed valproate in September 2021. A reduction of 7,256 from 27,448 in April 2018 to 20,192 in September 2021

Of the 20,192 females prescribed valproate in September 2021:

  • 1,738 (8.6%) were aged 0 to 11 years of age
  • 530 (2.6%) aged 12 to 15 years
  • 8,107 (40.1%) aged 16 to 44 years
  • and 9,817 (48.6%) aged 45 to 54 years.

Valproate prescribing and pregnancy

for conceptions identified since April 2018

  • Of the 49,599 females prescribed valproate832 females had a total of 938 conceptions
  • 247 of those females were prescribed valproate in a month in which they were pregnant
  • Of the 247 females, 25 were identified as new additions in the most recent 6 months, April 2021 to September 2021

Last edited: 19 July 2023 9:09 am