A woman at the centre of a high-profile kidnapping case has been denied bail by the Court of Appeal while she awaits the outcome of her appeal against a jail sentence for perjury.

Kay Skelton is nine months pregnant with her third child, and was concerned about having her child while in prison and how her two-year-old was coping without her.

She and her father, Dick Headley, were convicted in the High Court in Hamilton 2008 over the kidnapping of her son in 2006 when he was aged six as part of a custody dispute and sentenced home detention.

The boy was snatched from a Hamilton library and taken into hiding, before being given up five months later.

Skelton was convicted in Hamilton District Court of a separate perjury charge on July 21 this year, and on October 1 was sentenced to two years eight months' jail.

She appealed to the Court of Appeal against the length of her sentence, and was denied bail by Hamilton District Court pending her appeal.

She then applied to the Court of Appeal for bail.

The court was told Skelton had approval for her new baby to remain with her in prison after the birth, and was receiving maternity care.

Appeal court judge Justice Grant Hammond said Skelton had a history of frustrating the court process, using delaying tactics, and her stance had been described in the High Court as "outrageous in many areas"

"It is a matter of great sadness that a child has to be born to a woman who is incarcerated, he said.

"But the corrections system has long since had to deal with this problem."

Skelton had not shown that her case was exceptional, and the appeal for bail was denied.