One of Scotland’s first same-sex parents has failed in a landmark bid to strip a former partner of her ‘motherhood’.

The woman, who gave birth to twins after artificial insemination, is understood to be the first in Scotland to ever challenge the parentage of her children’s second mother.

She launched her case after the private hospital which helped her conceive, Nuffield in Glasgow, lost paperwork showing her former partner accepted parental responsibility for the two boys, now seven.

The birth mother filed for a declarator of non-parentage against her former partner, who has no biological connection with the twins, after a bitter split.

But her bid, under complex parts of the 2008 Human Fertilisation and Embryology Act, was turned down at Edinburgh Sheriff Court this autumn, according to a newly released judgment.

The landmark ruling underlines that same-sex parents, including non-biological ones, will have the same rights and responsibilities as everyone else when they decide to have a child together.

Sheriff Wendy Sheenan made her decision on the basis of evidence that the two women - who cannot be named to protect the identity of their children - were in a relationship and wanted to have a child together.

Sheriff Sheenan described claims by the birth mother - the “pursuer” who brought the case - that she had not been in a stable relationship with the non-biological partner as “baffling”.

The pair co-habited for some seven years until they split in 2014, four years after their children were born. It was in 2014 that the Nuffield hospital admitted that it could not find documents signed by the non-birth mother declaring parentage.

Sheriff Sheenan said these documents had been lost and that evidence before her from witnesses both at the hospital and friends and family indicated that the decision to bring the twins in to the world, by intrauterine insemination, was joint.

She said: “I did not accept the pursuer’s evidence that the relationship was not a committed one and that it was only a ‘partnership of sorts’. The pursuer’s evidence disclosed a level of disappointment and bitterness stemming from the difficulties between the parties in the latter part of their relationship and the breakdown of their sexual relationship.

“It was evident that she gave her evidence with an element of revisionism as to the nature of the parties’ relationship which was not borne out by the other evidence in this case.”

The sheriff dismissed as “nonsense” claims by the birth mother, who is identified as “L” in the judgment, that her relationship was falling apart by the time of the birth. She was also sceptical about L’s claim that she had reluctantly recorded the non-biological mother, referred to as “B” on the children’s birth certificates.

Sheriff Sheenan cited a male witness, a friend of the non-biological mother, B, saying both parties were happy with the registration.

Sheriff Sheenan cited the witness as saying “L’s details were recorded under the section ‘mother’ while B’s details were recorded under ‘father” “

He added: “As gay and lesbian citizens, we all felt this to be another example of bureaucratic institutions not keeping pace with changes in society. We all laughed at the absurdity of B being recorded as “father” but felt at the time that it was more important the boys were recognised legally as having two parents rather than just one.

“L was involved in this conversation and at no point did I feel that L was uncomfortable or being forced into doing something she did not want.”

B, in defending the action, said: “L and I were very happy, in love and excited about registering [our boys’] birth.

“It felt like the beginning of our lives together as a modern family. For me it was like a dream come true.

“It was also very exciting to be amongst the first same sex couples registering our children’s births and becoming legal parents. I was so happy that our children were beginning their lives within a secure and solid family unit.

“We had them with us when we went to the registrars to register the birth. We had taken a long time to decide on names.

“L and I were very proud and happy in the way that new parents are. It had been a challenging journey through fertility treatment and [one child]’s survival in the first few weeks of his life. “This journey had strengthened our relationship.”