Fairfax Media has spoken with three independent sources who have confirmed the women tried to end their lives, saying their children would be better off in life if they were dead.

"Their thinking is that if the babies have been born in Australia, they cannot be sent anywhere else, including Manus Island or Nauru," the president of the Christmas Island Shire Council, Gordon Thompson, said.

"It's a shocking conclusion to come to, but that's the state of helplessness in the centre at the moment."

The mothers became inconsolable when told this week that they would be sent to Nauru and Manus Island, saying they would rather die, lawyers told Fairfax Media.

Jacob Varghese, a principal at Maurice Blackburn Lawyers who is representing 72 asylum seeker babies, said the mothers had become extremely distressed when they were told by immigration officials that they would never be resettled in Australia because they had arrived after July 19, 2013.

People who arrived after this date will not be settled in Australia, as enacted by former Labor prime minister Kevin Rudd.

"We are gravely concerned about the welfare of the families on Christmas Island," Mr Varghese said.

"We have heard from our clients there that in the last day several women have attempted suicide or harmed themselves. They are in a state of utter despair. They are concerned about the health of their children."

Mr Varghese said that his clients, many of whom have newborn babies, feel like they are in a "living hell". One woman tried to hang herself, while others starting cutting themselves with glass, he said.

"Keeping children and families on Christmas Island is monstrous," he said.

"It is bad enough that we keep children imprisoned. But there is no sensible reason that families cannot be detained on the mainland where they would have access to the medical and welfare services they require."

According to section 4AA of the Migration Act, children should only be detained as a measure of last resort.

Many of the mothers and their children have been held on the island for nearly 12 months, Mr Varghese said.

Mr Thompson confirmed there had been women attempting suicide in the detention centre.

"They are saying, 'the babies have better chance at life if I am dead'," he said.

A spokesman for Immigration Minister Scott Morrison said: “It is longstanding government practice not to confirm or comment on reports of individual acts of self-harm.

It comes as figures show numbers in offshore detention centres have risen sharply with asylum seeker children more likely to be in detention camps than adults.

Figures from the Refugee Council of Australia show nearly a quarter of children (23 per cent of 4331) in Australia's immigration detention system are in detention centres, including 208 children in the Nauru centre.

This is in contrast to 18 per cent of adults being held in detention centres.

Figures also show many more asylum seekers are living in the community on bridging visas than in detention centres.

"The use of mandatory detention as a deterrent to people arriving by boat to seek asylum is one of the most unsuccessful of all Australian government policies,'' said refugee council chief executive, Paul Power.

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