Two same-sex couples who are contesting custody over two young girls have put their own wishes ahead of the welfare the children involved, according to a leading UK family judge.

Mr Justice Hedley was speaking in the High Court in a case in which a gay man and his lover took the lesbian mother of his children and her partner to court for access rights.

The case is similar to an Irish case in which a gay man, who acted as a sperm donor for a lesbian couple, sought access to his child. In that case, the Supreme Court ruled that the father should be given access rights.

The parents involved in the UK case were the mother of the two children and her lesbian civil partner, now aged 45 and 44 respectively, and the biological father of the girls and his long-standing gay partner, aged 50 and 41, according to a Daily Mail report.

Their names, and the names of the children, were kept secret under the ruling, which was published last week.

The couples met after the women placed an advert in The Pink Paper in July 1999 looking for “a gay man or couple who would like to start a family with a lesbian couple”. The men replied, saying “we would love to be father and stepfather”.

After the birth of the first child, the couples maintained friendly relations for several years, but ‘it all went wrong’ in 2008 when they fell into dispute over the children.

Mr Justice Hedley expressed frustration at the ‘lack of sufficient vocabulary to explain the true nature of the relationships’.

However, he was clear about the impact of the couples’ conflict on the two sisters in the case, saying at least one of them had suffered significant emotional harm.

“The four adults in this case regard the price paid by these two children as an acceptable price for the pursuit of their own adult disputes,” he said.

The adults involved were “intelligent professional people” who agreed to have children through IVF “with the agreement and co-operation of all parties”, Justice Hedley said.

But he warned: “The case provides a vivid illustration of just how wrong these arrangements can go.”

The judgment quotes a social worker who said the older daughter was caught in “a horrendous tangle of emotion and conflict that exists between these adults. The girl is being made to carry the responsibility for the failure of the adults in this system to overcome the conflicts between them.”

Mr Justice Hedley said there was ‘widespread concern at the welfare of the children’.

The two women should be regarded as ‘primary parents’ with the main responsibility for bringing up the girls, but the men should be regarded as ‘secondary parents’.

They should be consulted on issues of health, medical operations, education and moves of house. The judge also made a contact order so they could see the girls at set times.

Mr Justice Hedley said: “It is all too easy in these cases for biological fathers to see themselves in the same position as in separated parent cases in heterosexual arrangements, whereas this arrangement is, and was always intended to be, quite different.

“I have tried hard to see whether there are any other concepts than that of mother, father and primary carer, all conventional family concepts.

“The best that I have achieved . . . is to contemplate the concept of principal and secondary parenting.”

He said gay and lesbian couples should decide in advance who will bring up the children if they choose to have babies.

Linzi Bull of the law firm Harbottle & Lewis, which represented the men, said: “The case provides a very real warning to couples entering into artificial insemination arrangements.”