A whistleblower has claimed the unit at Wishaw General Hospital is cramped and understaffed, increasing the risk of infection and meaning premature babies do not receive the one-to-one care they need.
NHS Lanarkshire has insisted the department has appropriate staffing and that on rare occasions that the unit is full, babies are trans-ferred to other hospitals.
The health board said that it had contacted the British Association of Perinatal Medicine to provide "further assurance of the safety and effectiveness of our serv-ices" following the claims.
Junior MacLean died aged seven weeks on February 19 after contracting blood infection sepsis. Another baby died aged five weeks on March 10 after also being diagnosed with sepsis. It is understood an investigation had confirmed the deaths were unrelated and no cross contamination occurred.
Junior's parents have said he was repeatedly moved from intensive care to a side room due to pressure over space.
Dr Sam Ibhanesebhor, consultant neonatologist at Wishaw General Hospital, said: "The clinical facilities we have in the unit are excellent, as are the staff, and we are concerned at any suggestion that we would compromise the safety of any baby in our care.
"When a baby is in the neonatal unit it is a very traumatic time for the parents and we want to ensure they are confident about the high standard of services provided."