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What is FVSD?

Terms defining FVSD have changed and developed over time as research evidence came to light. 

Early research showed concerning numbers of children born with birth defects who were taking Antiepileptic Drugs (AEDs). There was an assumption at first, that Epilepsy itself caused these abnormalities.

Fetal Anticonvulsant Syndrome (FACS).  Initially it was seen as a syndrome, similar to Downs, or Ehlers Danlos.  There was uncertainty about whether it was inherited to some extent or was caused by a genetic defect.

The first group National Fetal Anticonvulsant Syndrome Association (NFACSA) adopted this term as it takes into account families that contacted them whose children were exposed to other AEDs.

The term Fetal Valproate Syndrome (FVS) was developed by researchers Jill Clayton-Smith and Amanda Wood, who were the first to denote a phenotype.

For patients, connecting the syndrome to the medical condition or directly to the drug was problematic, as too many personal questions would be asked about the mother's condition.  It was easier to call it “FACS”, for both the young people affected and their parents.

It is now (2021) absolutely clear and without doubt that sodium valproate causes significantly higher risk of congenital malformations (birth defects) (up to 30% on high doses) and important to use the term valproate in the name as it directly relates to one specific drug as the cause.

The name Fetal Valproate Spectrum Disorder takes into account that symptoms, but can vary greatly from person to person.  This often depends on the time at which the medicine affected the fetus during the pregnancy period.  

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