Health officials have granted a legally "complicated" surrogacy bid which will see embryos that have been stored overseas being flown to New Zealand so an Irish expat can try to carry a baby for her sister who lives in Europe.
And if the baby hopes come true, the baby's intended parents will then have to navigate their way through Irish laws to formally adopt the child.
As per New Zealand law, a fertility clinic acting on behalf of the birth and intended parents have made a surrogacy bid application to the Ministry of Health's Ethics Committee on Assisted Reproductive Technology (Ecart).
The application revealed the woman – who lives in Ireland - required a surrogate to carry a baby after undergoing a hysterectomy.
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She and her partner had previously created several embryos via IVF treatment which were stored in Ireland.
The woman's sister and her partner live in New Zealand.
Ecart granted the application – which it said involved an arrangement that was "complicated legally" - after extensively considering surrogacy laws in both New Zealand and Ireland, and adoption laws in this country.
But it recommended all parties took part in a joint counselling session in New Zealand. Both the intending parents and birth parents had undergone counselling in their respective countries, while a joint session via Skype had been deemed "not strictly counselling".
The committee – which works to the principles of the Human Assisted Reproductive Technology act 2004 - considers, determines and monitors applications made by fertility clinics for a range of assisted reproductive procedures and human reproductive research.
Procedures which need approval from Ecart include clinic-assisted surrogacy, donation of eggs or sperm between certain family members, and embryo donation for reproductive purposes.
The fertility clinic acting on behalf of the families said if the application was approved, and the New Zealand-based sister became pregnant, the Irish-based couple would travel here "for a short time" before the child was born.
"They will get a New Zealand passport for the baby who will go back with them as soon as possible and they will then apply for paternity," minutes of the meeting revealed.
In Ireland, surrogacy was not recognised.
And the Ireland-based hopeful parents would not be able to adopt the child under New Zealand law as they were not residents here.
Instead, once settled back into their home country, they would have a paternity test carried out on the hoped-for baby, before then being able to apply to adopt the child under Irish law.
Ecart member and Fertility Associates clinician and chair Dr Mary Birdsall told the Weekend Herald the case was "moderately complicated because of the different regulations that exist in different countries".
"And it has challenged us as a group," she said.
That included all parties undergoing the pre-requisite counselling required to identify any potential issues.
"It is certainly easier if all parties are based in the same country," Birdsall said.
But she added: "What a wonderful gesture for a sister to do. It is good that we live in a global community that this is possible."
Birdsall said in terms of New Zealand surrogacy cases, the surrogate was often related to the intended mother.
"The idea is that they would find someone that they knew and trusted to carry their baby and that they knew and trusted them enough to give them their baby back," she said.
"In New Zealand the person that gives birth to the baby is the baby's legal mother until she gives up that baby for adoption and chooses to have the genetic parents adopt their own baby.
"Many people do use within family members because that is who volunteers or comes forward."
The biggest growing surrogacy trend in New Zealand was same-sex men wishing to have a baby using a surrogate and an egg donor, she said.
Ecart chair Iris Reuvecamp said the case featuring the Irish sisters was not a "one-off", but she had not seen an increase of "applications of that nature".
Family law expert Margaret Casey – who is one of New Zealand's leading experts on international and domestic surrogacies – said she was also aware of several previous New Zealand surrogacy cases involving family members based in Australia or the UK.
"And [there have been cases] going other ways . . . where the surrogate lives in the other country and comes to New Zealand for an Ecart approved transfer, goes back to the other country and then comes back here to give birth," she said.
"There is . . . not many . . . they would have to be in the minority.
"But you can understand it. Who better to carry your child, but a member of your family? And how cool for the child to grow up knowing that too, that an aunt carried you."
A spokesperson for the Ministry of Health said the committee had received 20-30 surrogacy applications annually over the past three years.
"A large majority of these are approved," the spokesperson said.
Those that involved an intended mother and a surrogate based in different countries were "rare".