Two premature babies died after being infected with blood in the hospital's newborn unit.
The third is in a stable state after the infection with Staphylococcus aureus at Princess Royal Maternity Hospital in Glasgow.
On January 24, a specialist incident management team (IMT) was established to investigate deaths.
The local NHS health administration said the two who died were "very bad", and the infection was "one of several contributing reasons".
Dr. Barbara Weinhardt, a doctor of infection control, said "control measures have been taken", including deep, clean, isolating and barrier-nursing nurses, safety information for all employees, and infection control advice for all visitors. "
She added: "The results today confirmed that three cases of Staphylococcus aureus are related and our studies are continuing as they are.
"Staphylococcus aureus is a bacterium found in the skin and in the nasal tube that contains about one in four people and causes infection only when it enters the body.
"When people are vulnerable to infection, it can cause serious infection."
IMT consists of specialists, occupational health doctors, infection control doctors and nurses, as well as staff of manors and premises.
"Our infection control team continues to work closely with clinical colleagues and local staff to manage the situation and take all necessary steps to maintain patient safety," said Dr. Alan Mathers, Chief of Medicine, Services for Women and Children.
Deaths by Scottish Health Secretary Jean Freeman said last week that fungal infections associated with pigeon stools were "contributing factor" to the death of a 10-year-old boy Glasgow Queen Elizabeth University Hospital.
Prosecutors deal with the incident as well as the death of a 73-year-old woman who also had a cryptococcus infection.