A Russian man has sued an IVF clinic after his wife admitted that she had swapped his sperm for her lover's during treatment.
Maxim Anokhin only found that his one-year-old son was not his biological child when their relationship turned sour and his wife admitted to the swap, the Daily Mail reported.
Yana Anokhina, 38, had reportedly told the clinic she wanted the man she loved to be the father, but had let her husband pay for the treatment and kept him in the dark for the child's first year.
Mr Anokhin successfully sued the Moscow clinic which allowed the swap and was awarded $8970 in compensation for his moral and financial damages.
"I trusted my wife," he said. "I believed her and trusted her, 100 per cent.
"It means that when I was told about it… I was shocked… I was distressed, and I could hardly believe it."
A home video shows him feeding the young child.
The court found that he had paid for the IVF treatment and had provided his sperm believing that he would be the father of the baby.
Ms Anokhina has not spoken about the swap but reports say she wanted the father of her baby to be the man she loved - not her husband.
But for a year Mr Anokhin believed the child to be his and 'loved and supported' the boy, called Timofey.
Later the couple split and are now both in new relationships, the court was told. Mr Anokhin said his wife revealed the truth to him when they broke up.
"It was found out during the investigation in court that Maxim's wife Yana was the one who initiated the process of replacing her husband's biological material," reported Vesti.
"Allegedly, she wanted to give birth to a child by a man with whom she was in love, and her husband was the one who paid the costs."
DNA tests proved that Mr Anokhin was not the father prompting him to sue Kulakov Medical Centre which provided the IVF treatment.
Mr Anokhin's lawyer Olga Nemtseva said the clinic had a duty to her client and could not solely follow the wishes of his wife.
"Surely he would have been interested in understanding who exactly was going to be the biological father of his child," she said.
The court found that clinic staff assisted the woman in swapping the sperm, reported Vesti.
The doctor involved in their case, Liya Kazaryan, mentioned in the law suit, has refused to speak in detail.
"I am not giving any interviews… I do not want to say a word on this matter," she said.
But asked how a man could be certain he was the real father, she laughed: "Only a woman can be sure."
Denis Ivchenko, lawyer for Yana Anokhina, said he could not comment without his client's authorisation.
"Without her agreement I cannot say a word," he said.
Mr Anokhin said he took the case against Yana - now his ex-wife - not for money but justice.
"I wanted to make this matter public, so there are no more cheated men like me, cheated husbands, in the future," he said.
"It should not happen again."
Mr Anokhin now has another son born without IVF treatment to his new partner. He is now "happy" but "cannot forget the other little boy who for a year he called his son", reported Vesti.
Ms Anokhina is now in a relationship with the biological father of her baby.