A woman convicted of inflicting head injuries to her then three-year-old son has been told he is likely to need care for the rest of his life.

Itupa Julie Mikaio, 40, was today sentenced to a total of five years' jail on three charges relating to incidents in Auckland in June last year.

In September, a High Court jury found Mikaio guilty of wounding son Benjamin with intent to injure and neglecting to provide him with the necessaries of life by delaying getting medical treatment.

Mikaio admitted the third charge she was sentenced on - injuring with intent.

That count related to an assault on Benjamin three days earlier, when he was struck on the body with a shoe and left with broken bones.

Justice Forrest Miller said the head injuries the boy received in the later incident had left him with bleak prospects of leading a normal life.

He noted a paediatrician's evidence at trial that it was doubtful Benjamin, who now had difficulty walking and talking and needed to wear a skull cap when he went outside, would have independence as an adult.

Justice Miller said Mikaio had shown remorse and contrition, had no previous convictions and was considered to be at a low risk of offending.

He also accepted that Mikaio was under stress at the time through being pregnant and having four other children as well as Benjamin to look after.

However, serious violence had been involved, the attacks had been prolonged and Benjamin had been vulnerable.

The judge said Mikaio had also sought to excuse herself "by advancing the fanciful notion" that the head injuries were the result of an accident.

Mikaio was charged after Benjamin was taken to Starship Hospital unconscious.

During the trial, the court was told that Benjamin was brought up by his paternal grandmother in Samoa between 2004 and 2007, when he went to live with Mikaio in Auckland.

However, mother and child had trouble bonding, and Mikaio found Benjamin troublesome and was also upset by his bedwetting.

The cause of the assault in which Benjamin received his head injuries was apparently because he had wet his bed again.

After that attack, Benjamin collapsed and Mikaio, who covered him with blankets and prayed for him, waited five hours before seeking help from a Samoan faith healer, who told her to get an ambulance.

Justice Miller said Benjamin had nearly died from internal bleeding and he drew the inference that the damage to his brain could have been materially reduced if an ambulance had been called earlier.

The defence had argued that Mikaio was not aware of how serious the injuries were.

- NZPA