The error only came to light when the babies were born, court papers say
A couple from New York are alleged to have spent $140,000 (100,000 USD) on fertility treatment, only to give birth to twins which weren't biologically theirs.
The couple, known only as Y.Z and A.P., have filed a lawsuit against a Los Angeles clinic, CHA Fertility Center, claiming they mixed up their frozen embryos with those belonging to two other couples.
The clinic was supposed to have thawed two female embryos and implanted them into A.P, but as her pregnancy progressed scans showed she was carrying twin boys the lawsuit alleges.
At first, the Asian couple believed the scans might be wrong and excitedly prepared for their new arrivals, the New York Post reported.
But when A.P. gave birth to baby boys, neither of whom were of Asian heritage, their worst fears were realised, the court papers claim.
DNA tests showed the baby boys were not related to the couple, or to each other.
According to the lawsuit, the couple were then forced to hand the babies to their biological parents, who were also clients at the IVF clinic.
The husband and wife described the experience as a 'devastating loss' and are seeking unspecified costs. The clinic did not respond to the Post's request for comment and has not yet publicly responded to the claims.