A German man who fathered four children with his sister has failed to get his conviction for incest overturned at the European Court of Human Rights.

The court ruled that Germany’s criminalisation of sex between siblings is justified for the protection of marriage and the family, the Daily Telegraph reports.

Patrick Stuebing had argued that his sexual relationship with his sister is not abnormal, and that Germany has interfered with his rights to privacy and a family life.

However, judges at the European Court of Human Rights (ECHR) said that Germany’s ban on incest was “aimed at the protection of morals and the rights of others”.

It held that the human rights of Mr Stuebing were not violated when he was sent to jail for three years in 2005 for his sexual relationship with his sister. Mr Stuebing had been adopted when he was a small child and only met his sister as an adult.

The judges cited several justifications for the law’s existence, including “protection of the family” and “self-determination and public health,” which are “set against the background of a common conviction that incest should be subject to criminal liability.”

The ECHR said the German courts did not convict Ms Karolewski, Mr Stuebing’s sister, because she had a personality disorder and was “only partially liable” for her actions.

Mr Stuebing, who was born in 1976, was placed in a children’s home at the age of three and was adopted at seven years old.

He tracked down his biological family when he was 24 and only then became aware of the existence of his sister.

Following the death of their mother, the brother and sister’s relationship “intensified”. Soon afterwards they had sexual intercourse and between 2001 and 2005 had four children.

Three of the children now live in care and two are disabled.

Mr Stuebing can still appeal to the Grand Chamber of the ECHR, whose decision will be final. He has three months to appeal.