In France, roughly one in a thousand pregnant women take valproate, a drug used in treating epilepsy (brand name Depakine) and bipolar disorder (brand names Depakote or Depamide). According to a study [original source, French, BBC] released by France's drug regulator, the children of those mothers are at serious risk of being born with severe congenital malformations: between 2 (Depakote, Depamide) and 4 (Depakine) times more likely than the general population.

The drug, of pharmaceutical company Sanofi, has been sold in a number of global markets, including the US, China and the UK. In a number of countries, including the US, it is also being used in the prevention of migraine (see 4th para), according to the European Medical Agency (EMA).

The French study estimates the total number of victims at between 2,150 and 4,100 over the period the drug was sold in France, starting from 1967. A rough extrapolation based on population size only, indicates that there could be between 10,000 and 20,000 similar victims in the US. While the French regulator will release a detailed study on the congenital defects (neural tube defects, cleft palate) only in September, EMA already registered delayed walking and talking, memory problems, difficulty with speech and language, lower intellectual ability, increased risk of autistic spectrum disorder and a higher likelihood of ADHD symptoms.

Sanofi itself has warned since 2011 that the drug should not be taken during pregnancy. Both the US FDA, in 2013, and the EU's EMA, in 2014, have warned healthcare professionals that valproate sodium and related products, valproic acid and divalproex sodium, should not be prescribed to pregnant women or women who are trying to get pregnant, unless no substitute is available.