Nearly half of very premature babies born in England and Wales are missing out on development checks designed to spot serious disabilities early, according to a new report.
The Royal College of Paediatrics and Child Health (RCPCH) said it found no evidence of two-year follow-ups for 46% of premature babies, suggesting neonatal units are either not recording the checks or are failing to carry them out.
The body, which is responsible for training and auditing paediatricians in the UK, said it had "major concerns" conditions such as cerebral palsy, visual impairment and intellectual developmental delay could be missed and go unnoticed until later in childhood.
Failing to carry out the checks could lead to "specialist care being delayed", the report added.
NHS guidelines say premature babies born 10 weeks early should be given a development check up at two years old to ensure they are developing normally, as they can be more vulnerable to disabilities.
The RCPCH's national neonatal audit programme (NNAP) analysed the data of 86,000 newborns needing specialist neonatal care in 2014, of which 3,656 were born before 30 weeks' gestation.
Dr Sam Oddie, clinical lead for the NNAP said: "When a baby is born very prematurely, they are born before they are physically ready for life outside the womb. This means they often have health problems, which can extend into childhood.
"To ensure they are developing as they should be, it is crucial that these babies are monitored closely from birth, at least for the first couple of years. So the fact 46% of babies had no developmental data entered at age two is a major concern.
"Not only does this create added anxiety for parents about whether their child's developmental milestones are being met, it also adds pressure to the health service as such children will need to begin a new pathway through the NHS."
The audit also found 11% of parents had not been consulted by doctors within 24 hours of their child's admission to a neonatal unit, which Dr Oddie said "has to change".
"Another cause for concern in findings is the lack of recorded discussions with parents at some neonatal units," he said.
"For a parent of a sick or premature baby, receiving a detailed explanation of their child's illness and treatment is a much needed comfort in a sad, and often daunting, situation."