click here to watch our interview with Kate Brian.

Breakfast talked to Kate Brian has had two children using the IVF method. She has also written about it. She said:

"This is going to have a big psychological impact."

People are going to be worried about this story. There are already questions over embryos. Some of the women she has spoken to are worried about what happens to their spare eggs. There's a big psychological impact, IVF is already traumatic enough without this shadow being cast.

Breakfast also talked to Barbara Hutchinson from the British Association for Adoption and Fostering. And to Clare Gorham, a black film maker and transracial adoptee.

Click here to watch our IVF discussion

IVF involves mixing sperm from the man and eggs from the woman together in the laboratory, before they are placed in the woman.

When the babies were born, the couple noticed that they were clearly dark-skinned, and suspected that something had gone wrong.

Possible errors

Professor Ian Craft, director of the London Fertility Centre, said mistakes have been made before.

We just cannot afford to have these things happen

Professor Ian Craft

He said it was probably time for the regulatory body to consider tighter rules.

"I have been aware of a situation at another centre whereby one couple received the wrong sperm from someone from a different ethnic group.

"I fear that they might now be recommending that we have an extra layer of administration, but perhaps we should - we just cannot afford to have these things happen."

Dr Vivienne Nathanson, of the British Medical Association, said that legally the woman who carries a child is the mother, regardless of its genetic inheritance.

American baby

An American mother, Donna Fasano of New York, gave birth to another couple's baby in 1998.

Ms Fasano, who is white, gave birth to a black child and a judge ordered that she should hand the infant over to his biological parents.

In Holland, suspicions were raised when a woman called Wilma Stuart, who is white, gave birth to dark-skinned twins in 1993.

DNA tests showed the hospital had mistakenly mixed sperm from her husband with that of a black man from the Dutch Antilles. She kept the twins.

The Human Fertilisation and Embryology Authority said inspections were regularly carried out to ensure that clinics met standards set out in its code of practice.

"Clinical and scientific inspectors check that clinics have procedures in place to double-check the identification of the individuals undergoing treatment, the sperm and eggs at the time of insemination and the embryos and the patient at the time of embryo transfer."