China will provide safe havens for parents to abandon unwanted children across most of the country, despite debate on whether they could see more babies dumped, state media reported.

The country has set up 25 so-called baby hatches in 10 provinces and major cities since June 2011, the official Xinhua news agency said Sunday. More will be built in another 18 regions, it added, citing the China Centre for Children's Welfare and Adoption (CCCWA).

The havens usually have an incubator, a delayed alarm device, an air conditioner and a baby bed, the report said.

Welfare staff retrieve a baby five to 10 minutes after a person leaves the child and presses the alarm button, allowing families to give up the infant safely and anonymously.

In most cases the children have severe illnesses or disabilities such as Down syndrome or cerebral palsy, it added.

Many babies are given up because parents cannot afford expensive medical bills and fees for special education, Xinhua said.

A disabled child can be a huge drain on a family's resources, and the limits imposed by the country's one-child policy can also be a factor.

The facilities have been praised for helping save the lives of children who would otherwise be abandoned in the street and as a mark of social progress.

But they have also sparked concern that their existence encourages parents to abandon unwanted babies, which is illegal, Xinhua said.

A baby hatch in Guangzhou received nearly 80 children aged between two days and five years in just two weeks after it opened on January 28, it said.

But Li Bo, head of the CCCWA, played down the concerns, adding that since the first facility was established in the northern city of Shijiazhuang, it has received children at about the same rate as the city's social welfare institution did in the previous two years.

"Laws emphasise prevention, while baby hatches focus on rescue after the laws are broken," Li was quoted as saying.

Han Jinhong, head of the Shijiazhuang social welfare institution, said that previously around two thirds of abandoned babies died, but the fatality rate had fallen sharply as a result of the baby hatch, Xinhua said.

"Although we cannot change the abandonment of babies, we can change the results after they are dumped," added Han.