It has been prescribed since 1978 and reports of the ingredient sodium valproate causing birth defects such as spina bifida go back almost as far. FACS is believed to have affected up to 20,000 babies – ten times more than Thalidomide.
FACS is, Dr Turnpenny points out, less dramatic than the missing and distorted limbs caused by Thalidomide, but the neurological effects are far worse. ‘About ten per cent of foetuses exposed to sodium valproate will have a major congenital malformation such as cleft palate. Twelve per cent are likely to be diagnosed with a neuro-developmental disorder.’