A New Zealand woman will carry and give birth to her own sibling, after being given approval to act as a surrogate for her mother.

It was believed to be the first approval by the Ethics Committee for Assisted Reproductive Technology (Ecart) of an application from a daughter to carry her mother's child, although there had been approvals for women to carry their own grandchild, The Sunday Star Times reported today.

The surrogate was one of four siblings and had two children of her own.

Fertility New Zealand chief executive Michelle Collyer praised the woman's decision to be a surrogate for her mother, calling her an "admirable daughter".

She said the case highlighted the growing problem of "social infertility", assuming the older woman had waited until too long in life to have another baby, possibly with another partner.

Ecart was set up in 2005 to consider all applications for surrogacy and fertility procedures in New Zealand.

It had heard 69 surrogacy applications, which made up about 65 per cent of all fertility treatment applications it received.