Health Minister Annette King is seeking advice over plans to film an actress giving birth for a porn movie.

A High Court judge last week ruled Vixen Direct owner Steve Crow could film the woman - known only as Nikki - in labour and giving birth, but he banned use of footage of the baby for the porn film, Ripe.

Justice Paul Heath declined an application by Child, Youth and Family to be given wardship of the unborn child and has instead appointed Nikki an agent of the court.

The actress and Mr Crow have been threatened with jail if they do not comply with the order.

Waikato Hospital sent a letter to Nikki three weeks ago banning the filming of her labour and birth in its delivery suite for "unlawful purposes".

Mr Crow said he would challenge the move.

"The ruling quite clearly shows they [the hospital] are on thin ground, legally," he said.

A spokesman for Annette King said she was seeking advice on the issue over what action she should or could take and also to assist the district health board.

Child, Youth and Family's chief social worker had sought guardianship of Nikki's unborn child and a court order to prevent filming of the birth.

Justice Heath delivered a 45-page decision last week in which he said: "I do not accept that Nikki has thought fully about the consequences, in the future, of involvement in a pornographic film.

"I find myself in total agreement with the chief social worker's conclusion that Nikki's desire to be a 'star' has, in fact, over-ridden her judgment about what is in the best interests of the unborn child."

Nikki has been in Waikato Hospital's antenatal unit since Tuesday with pregnancy complications. The use of her real name in any reporting on the issue is banned.

Justice Heath has adjourned the case until December 18 "to ascertain what steps have been taken since the making of these orders".

He said if undertakings were filed and deliberately breached he would consider it "a very serious breach of court for which likely punishment would be imprisonment".