'Many women don't realise they may be vulnerable'.

Diane Dyson is a nurse dedicated to helping mums whose experience of a pregnancy or child birth has not run smoothly and may be in need of specialist help.

With more than 20 years in the frontline as a mental health nurse, Diane is part of a team whose aim is to pull through women that face real personal and desperate problems around the time of childbirth.

The expressions of 'baby blues' or the all-encompassing diagnosis of post-natal depression do not accurately describe the mental health problems some women develop that requires the specialist help of experts.

Diane, together with nurse colleague Alison Collins, a dedicated team of mental health nurses and consultant psychiatrist Dr Sue Smith now have a specialist Mother and Baby Unit at Cardiff's University Hospital of Wales for mums who face the unexplained problems of mental illness during and following child birth.

The three-bed centre is one of the smallest in the UK and reserved for the most serious cases but Diane's main work is to support, help and reassure mums in their own homes.

Together with colleagues her caseload of 150 mums a year is based in Cardiff and the Vale of Glamorgan but Diane also works in the Valleys and Merthyr providing expert help.

'Childbirth is a significant trigger for mental illness and many women do not realise they may be vulnerable.' Unknown to them there may be a family history of mental illness which increases their risk, or the birth itself can be a trigger. There probably isn't one real cause and it's often a combination of factors that push people to breaking point. Post natal depression can range from mild to severe and most women will be looked after by their GP and health visitor, but more severe cases will need the help and advice of a psychiatrist or specialist nurses.

She said: 'The more seriously ill women may be admitted to the Mother and Baby Unit for anything from a few days or up to several months.

'Midwives check if there is a personal or family history of mental illness when a woman attends her first ante-natal appointment.

'An important issue is the use of drugs used to treat mental health problems especially during pregnancy, as medication which is vital for the mother may in some cases be harmful to the foetus. But taking the mother off their medication may place their mental health at risk. It is a difficult decision for women to make but they should know there is a specialist team in Cardiff that can help.'