Assisted reproduction, fertility treatment, donor conception and co-parenting

Our team of leading fertility lawyers provide expert legal advice on all forms of assisted reproduction, fertility treatment, donor conception and co-parenting to help you create and protect your family.

We know that there are lots of different ways people form families from assisted reproduction and fertility treatment which may or may not involve the use of a donor, to co-parenting arrangements where people who are not in relationships together choose to have and raise a child together.  

Navigating issues around who will be treated as a legal parent (which is not always who you intend) and what involvement in your child’s life everyone will have can be tricky and we can help you address the issues whenever they arise. We also know when couples separate there can sometimes be issues around what should happen to any stored embryos.  

Our lawyers

Our specialist team of fertility and children lawyers act for individuals and couples who use assisted reproduction/fertility treatment to conceive, sperm and egg donors, co-parents and fertility clinics.  

  • Advising the ex-partner of the legal mother who had been in a relationship (but not married or civil partnered) at the time of child’s conception and did not complete the appropriate consent forms at a UK licenced fertility clinic to be a legal parent. The ex-partner was subsequently registered on the birth certificate for the child. We advised on a declaration of non-parentage and applications for parental responsibility for the ex-partner and a child arrangements order to spend time with the child.  
  • Advising a mother who was not in a relationship but intended to conceive a child and co-parent through fertility treatment with a friend.  
  • Acting for a leading fertility clinic in a number of reported cases involving declarations of parentage where unmarried couples had used sperm donors to conceive and there were errors in the consent forms used for the partners to become legal parents. This included where parents had subsequently separated and were not in agreement about who was a legal parent.  
  • Acting for a mother in an application for a declaration of parentage following IVF treatment with her then same-sex partner where there were problems with the consent forms for legal parentage completed at a UK fertility clinic and it was unclear whether the same-sex partner was a legal parent. The issue arose several years after the child’s birth. We were able to secure the clinic’s agreement to pay the mother’s costs for the declaration of parentage. As well as providing certainty for her child, the mother was able to pursue child maintenance from her ex-partner.  

What you need to know

In the UK, the legal mother will always be the person who gives birth to the child. Who else is a legal parent will depend on how the child was conceived, whether the legal mother was married or in a civil partnership, whether fertility treatment took place at a UK licenced fertility clinic and what consent forms were completed prior to treatment. In some circumstances a sperm donor may be treated as a legal parent even if you do not intend them to be.  

Legal parentage can affect a wide number of issues for parents and children including nationality, inheritance, parental responsibility, child arrangements and financial responsibility for a child.  

We help parents and donors navigate these issues at whatever stage they arise, whether pre-conception including advising on the appropriate clinic forms that need to be completed for treatment at a UK licenced fertility clinic and preparing pre-conception agreements or after a child is born. 

Even if someone is not a legal parent they may be able to make applications for parental responsibility or a child arrangements order (often referred to as residence or contact orders).  

We know that sometimes issues only arise when things go wrong. We can help you deal with disputes where there is uncertainty about who is a legal parent, if there is a dispute as to what should happen to stored embryos or if someone you agreed would be a donor is seeking to become involved in your child’s life.  


Vlogs from our legal experts

In this vlog, Caitlin Jenkins, the familylawvlogger talks to her Mills & Reeve specialist children law colleague, Rose-Marie Drury, about the concept of Legal Parentage and the implications of this for those who conceive a child using a donor or through surrogacy. To find out more or to contact Rose-Marie or one of her colleagues in the Mills & Reeve specialist children team please go to

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