A bungled IVF treatment — which led to a New York woman unknowingly giving birth to the babies of two couples who were complete strangers — has been branded the "worst embryo-related tragedies in history".
Incredibly, the horrifying mix-up only came to light when the woman gave birth to the baby boys — who she believed were her own biological twins — and discovered they were of a different ethnicity to herself and her husband who are Korean-American.
The babies have since been reunited with their biological parents leaving the New York couple, who spent $US100,000 ($A143,600) on fertility treatment, with "permanent emotional injuries from which they will not recover".
They are now suing the fertility centre along with Anni and Ashot Manukyan, one of the other couples embroiled in the debacle, news.com.au reports.
The "heartbreaking" mix-up originally occurred in August last year when the embryos of three separate couples, who were all being treated at the Los Angeles CHA Fertility Center on the same day, were implanted into the wrong women.
Anni and Ashot Manukyan, who are biological parents of one of the baby boys, have revealed that not only was their embryo given to the wrong person, Anni was implanted with yet another stranger's embryo in its place. However, this procedure did not result in a pregnancy.
The Manukyans, of Glendale, California, are now suing Los Angeles CHA Fertility Center after the clinic placed two embryos — one belonging to them and one to another couple — into the woman from New York.
The shocked parents, who also have an older daughter, said they didn't even know that they had a son until after he was born on March 30.
Disturbingly, they were only able to meet their biological son Alec more than a month later after winning a turbulent custody battle, the distraught couple told a press conference in Los Angeles on Wednesday.
Alec was six weeks old by the time they met him for the first time, an encounter that happened in the lobby of a hotel.
"Who wants to meet their child in the lobby of a hotel?" Anni said through tears at a press conference in Los Angeles on Wednesday. "It was heartbreaking. It was terrible," she sobbed.
"It is important to us as a family that this never happens again. Without our knowledge, CHA implanted our embryo into another woman," she added.
Anni revealed in video shared by their lawyers Peiffer Wolf Carr Kane on YouTube, that it only emerged that Alec had been born after they were asked to come into the centre for cheek swabs on April 11, which at the time was passed off as a routine procedure.
However, the next day, they were called back in again and this time were greeted by a doctor and a psychologist who informed them that the swab was in fact a DNA test, confirming that they were the biological parents of a boy delivered by another woman, also a patient at CHA, on March 31 in New York.
Anni and Ashot also learned the woman who had birthed Alec had given birth to two boys, with one belonging to a third couple who'd had their embryos on ice at CHA.
In a shock twist, Anni later learned she had been inseminated with an embryo belonging to a third couple who were clients of the clinic — but CHA has no idea who.
They are now suing the clinic, with their lawyer Adam Wolf calling their case "one of the worst embryo-related tragedies in US history".
The horrendous mix-up was revealed in a legal case filed last week by the New York couple who tried for years to become pregnant before giving birth to two babies belonging to two other families.
The Korean American couple, also a client of CHA, were told they had conceived twins, but the tragic mix-up became clear when the woman gave birth to two children of another ethnicity.
Married in 2012, the Asian husband and wife — identified in court papers only as Y.Z. and A.P. — turned to CHA Fertility Center, when their countless attempts, both natural and with artificial insemination, failed.
In their legal claim, the New York couple said the experience of delivering the babies and then losing them has left them with "permanent emotional injuries from which they will not recover".
They said they had chosen the clinic after being assured it was one of the top centres in the country.
The third family — who remains anonymous — has also been reunited with their son.
All three couples were at the clinic on the same day in August 2018 to have embryos transferred.
CHA declined to comment.
Anni Manukyan said she felt "violated" after she learned she had also been implanted with another couple's embryo that did not result in pregnancy.
"CHA robbed me of my ability to carry my own child, my baby boy, and be with him in the first moments of his life," she said.