LANDMARKS worldwide, including Canberra and Melbourne, were lit up purple yesterday for World Prematurity Day in honour of the 15 million babies born too soon worldwide.

Warwick Hospital maternity unit manager Ross Newton said the outlook was positive for the majority of premature babies with ongoing medical advancements.

"The ability to care for babies born at 24-28 weeks has increased, so more survive than previously," Mr Newton said.

"Some of the changes are only small but have led to huge advancements."

A premature baby is one born before 37 weeks gestation, and early premature babies are those born at 32 weeks or earlier.

"We have on average five premature babies born (at Warwick Hospital) per year out of about 200 births," Mr Newton said.

As a level three facility, Warwick Hospital generally offers care for babies born at 37 weeks or later.

Most expectant mothers who are likely to experience premature birth are transferred to better-equiped facilities in Toowoomba or Brisbane, depending on the gestation.

Mr Newton said that the Toowoomba Hospital could care for babies from 32 weeks gestation, with those born earlier or with significant health issues cared for in Brisbane.

"We have an excellent team on hand if needed, but the goal is usually to transfer mum and bub intact," he said.

"We can then accommodate mum and bub again once their care is able to be provided here."

Mr Newton said most babies remained in hospital until near the actual due date, although that can vary depending on complications and the gestation time.

The three main causes for premature births at Warwick Hospital were premature labour, ruptured membranes and pre-eclampsia, Mr Newton said.

There is also a slightly higher percentage of prematurity for multiple births.

Child health nurses Cathy McCosker and Noela Arundel from the Warwick Child and Family Health Centre said they have seen at least four early premature babies born weighing less than 1000 grams this year.

"On average we see about one premature baby per month through the clinic," Mrs McCosker said.

"Each mother gets two home visits under the Mums and Bubs program, but premature babies usually need more.

"Reflux is a very common problem with premature babies as well as respiratory issues."

Premature babies require follow-up appointments to check for eye, respiratory, growth and development issues.

Milestones are usually based on the corrected age rather than actual age for the first 12 months for babies born between 37 and 32 weeks.

Correction is ongoing for two years for those born earlier, or in some instances, specialist advice may be to work on the corrected age for longer.

Immunisations are still given on the actual age though, as it is important that the babies have the protection they need, the nurses said.

Mr Newton said overall, the majority of premature babies do catch up over time.