Neonatal staffing levels across Wales is cause for 'serious concern', according to an inquiry by the National Assembly Committee.
Around one in nine babies born here are admitted to one of Wales' 13 neonatal units each year.
But the Children and Young People Committee heard that a shortage of trained neonatal nurses is affecting every health board.
It also found the nurse-to-baby staffing ratios 'far from meet' the benchmark set out in the All Wales Neonatal Standards.
According to the Committee, the shortage has resulted in a number of health boards relying on paediatricians rather than dedicated neonatologists to support their neonatal services - a move the Committee describes as 'alarming'.
It's now calling on the Welsh Government to ensure all health boards have plans in place for dealing with staffing shortfalls.
– Christine Chapman AM, Chair of the Children and Young People Committee
While we recognise that recruitment and reconfiguration exercises have been introduced in many areas across Wales, we remain extremely concerned about medical and nursing staffing levels in local health boards across Wales.
We know that staff in neonatal units across Wales work under intense pressure, and we believe that there is an over-reliance on the goodwill and dedication of professionals to keep under-resourced units running.
The inquiry was set up to assess the Welsh Government's progress since a previous inquiry two years ago found that units at Welsh hospitals were 'understaffed, ill-equipped and over-capacity'.
A report at the time made 18 recommendations, all of which were accepted by the Welsh Government.
Ms Chapman went on to say that although progress has been made since then, more improvements are needed.
The Children and Young People Committee also found that more must be done to ensure that babies requiring special care are occupying the most appropriate cots for their needs - with access to high-dependency cots a particular problem.
The Welsh Government says it 'acknowledges further improvements are needed' and believes 'service change across NHS Wales will help deliver these improvements.'
– Welsh Government spokesperson
The Committee's inquiry highlights issues already identified in the Government's plan, Together for Health, such as recruitment and training of certain medical staff and some specialist services being spread too thinly.
Together for Health puts the case for modernising services. Creating specialist centres of excellence, alongside more care closer to home, will improve quality of care.
Local health boards are developing plans to improve their services and meet the aims of Together for Health. Health boards are considering issues such as medical recruitment and training, transport and population needs.
An independent group of medical experts, the National Clinical Forum, is reviewing health board proposals, which are also subject to public consultation.
Bliss, the charity for premature and special care babies, says it welcomes the inquiry's findings.
– Andy Coles, Bliss Chief Executive
This is an opportunity to improve the care provided to sick and premature babies and their families, which should be actioned without delay.
In recent years there has been significant progress in improving neonatal services. However, there is still much more to do to ensure the very best care is delivered to these vulnerable babies and their families in Wales.