The European Medicines Agency is holding a public hearing in London to consider whether current advice against taking the epilepsy drug sodium valproate while pregnant is not strong enough.
In 2014, the agency conducted a review and strengthened the restrictions on valproate-containing medicines, due to the risk of malformations and developmental problems in children exposed to the drug in the womb.
Valproate, also known as Epilim, has been licensed in Ireland since 1983 and to a lesser degree is used for hydrocephalus and cerebral palsy.
Epilepsy Ireland says the estimates from 2013 are that the drug has affected at least 400 children with birth defects and developmental issues here.
The new review by the EMA started in March and follows concerns particularly in France about the effectiveness of measures introduced following the previous review in 2014.
The French report suggested that over 4,000 children were born with malformations since 1967 following exposure to the drug in the womb there.
The HSE published a report on the drug in March of this year. It found that the drug was given to around 1,600 women aged 16-44 years between 2008 and 2013 here.
An Irish woman, Karen Keely, has given evidence at the public hearing about how she believes her three adult sons were affected by the drug.
Ms Keely told the hearing that at last families feel they are being listened to.
She said she was the mother of three adult boys - Harry, Lee and Lorcan - all affected by the drug, two of whom require life-long care.
She said they would never have a normal life, get married or have children.
Ms Keely said there needed to be properly funded public information campaigns about the drug, which include the brand and generic names.
She asked how many people read patient information leaflets in medicine boxes and called for warnings on boxes of the drug, which did not exist in Ireland.
Ms Keely also said one of the problems was that some patients on valproate long term may get the medicine in a plastic bag.
She called for a national register in Ireland of those who were on the medicine and people who are being prescribed it in the future.
She also wanted more research into the scale of the problem and accountability. Ms Keely said the HSE had information online but wider publicity was needed.
She was speaking as a representative of the Irish group FACS Ireland.
She also said repeated efforts to discuss the issue with Minister for Health Simon Harris had been fruitless.
Ms Keely told the hearing that better supports were needed for families affected.
This is the first EMA public hearing and the findings of the safety review will be issued at a later stage.
Earlier this year, the Foetal Anti-Convulsant Syndrome Forum, an umbrella of patient and disability organisations called on the Government to undertake an investigation into the current and historical use of the drug.
The HSE has a toolkit on valproate on its website and says it is important that valproate therapies are not prescribed for girls or women of child-bearing age, unless other treatments are not effective or are not tolerated.
It says the appropriate information should be given to all women on valproate treatment and the checklist should be completed.