16/12/2016 11:26 GMT | Updated 17/12/2017 05:12 GMT

Three Person Babies: Who Do We Recognise As Parents And Why?

The Human Fertilisation and Embryology Authority's (HFEA) decision to permit the licencing of fertility treatment involving genetic information from three people has sparked a renewed debate about who should be recognised as the parents of a child. The HFEA's decision does not alter the legal position, but society's perceptions of who is a parent remain in a state of flux.

English law provides that the person who gives birth to the child is automatically the legal mother, and the man who undergoes fertility treatment with that woman is the legal father regardless of whether it was his sperm that was used to create the child. This approach was followed when Parliament introduced provisions for same-sex partners and so both people undergoing fertility treatment together may be recognised as the legal parents of the child. Parliament stopped short of allowing two women both to be classed as mothers and two men as fathers. Instead it introduced the concept of "second legal parent" to cover same-sex couples. In these instances, a child will either have a legal mother or a legal father and the other parent will be termed their second legal parent. In reality, families choose to use whatever terminology they wish to describe their roles in day-to-day life, and so the 'second legal parent' concept has not made it into mainstream usage.

The law only permits two people to be classified as the legal parents and yesterday's decision does nothing to alter that. In some respects, it is now less important in legal, if not symbolic, terms to be regarded as the legal parent, as the law has uncoupled the automatic link between parenthood and the powers and duties of a parent. The Children Act 1989 allows for multiple people to have parental responsibility for a child even if not as a legal parent. Parental responsibility recognises the social relationship between the adult and the child rather than any genetic connection between them. As parental responsibility recognises the ongoing role that an adult plays in the upbringing of a child, it would not be accorded to a woman involved in assisting a couple to have a healthy child under the terms announced by the HFEA.

Legal motherhood is still firmly grounded in biology, however. But it is pregnancy rather than the origin of the egg that determines who is recognised as the mother. Consequently, a woman acting as a surrogate is regarded as the legal mother, not the woman who provided the egg. This remains the case even if the egg donor is the person who entered into the surrogacy arrangement with the surrogate and is the intended mother of the child. In rare cases this may create difficulties as surrogacy agreements are not legally enforceable in Britain for making a surrogate give up the child to the intending parents. The intending parents may both be the biological parents of the child but only one of them, the man, may be regarded as the legal father and only then if the surrogate is not already married or civil partnered and her spouse did not consent to the fertility treatment.

Biological origin still holds some sway when legal fatherhood is determined, but this too has been modified over time and legal fatherhood is by far the more challenging legal parental status to determine. Sometimes the man who is the biological father of the child will be regarded as the legal father, for example the man undergoing fertility treatment which used his sperm with the intention of him becoming the father. But generally, a sperm donor at a licensed clinic will not be classed as the legal father. Biology is important when a man provides sperm on an informal basis outside a clinic setting to a female same-sex couple who are cohabitees - he would be the legal father in that situation. But if they were married or civil partnered then he would not be the legal father. The couple's relationship determines whether it is biology or their legally registered union that makes the difference.

Regardless, society still holds a strong association between biology and notions of parenthood even though Parliament broke this link in 1990 when the first Human Fertilisation and Embryology Act was introduced. Arguably, the link had already been severed centuries ago when adoption legislation permitted an adult to be recognised as the legal parent of a child who was not their biological offspring. But some attitudes towards adoptive parents suggest that there are still some who consider biology to be at the heart of who is 'the real' parent of a child. Advances in reproductive technologies seem to have done little to dislodge those views, nor have changes to the law.