KING SOLOMON famously demonstrated his judgment in the case of two women who came to see him carrying a dead baby and a living one. Each claimed the living child as her own. Solomon ordered that the living child be cut in two and that half be given to each mother. When one woman gave up her claim rather than see the child killed, Solomon at once recognised her as the true mother.

But compared with a case due to start before the Court of Appeal today, Solomon had it easy. Natallie Evans launches her appeal against the judgment of Mr Justice Wall, given in October last year, that her frozen embryos be destroyed. Her case raises a host of complex issues that evoke profound sympathy as much as the need for fine legal reasoning.

Evans, 32, from Trowbridge, Wiltshire, had her ovaries removed during treatment for cancer in 2001. At the time she was engaged to Howard Johnston, with whom she had been trying to start a family. Before the treatment for cancer, Evans and Johnston underwent IVF treatment at the Bath Assisted Conception Clinic. They were advised that both of them needed to consent to the creation, storage and use of the embryos that the IVF process would produce and that either could change his or her mind at any time until the embryos were used.

Evans and Johnston signed the consent forms and the IVF treatment took place. Six embryos were created using Evans’s eggs and Johnston’s sperm. The eggs were placed in storage because Evans was advised to wait up to two years before implantation. But before this could happen the couple’s relationship ended, and, though initially willing to let Evans use the embryos, Johnston subsequently changed his mind and withdrew his consent, insisting that the embryos be destroyed.

Evans has since been fighting to preserve the embryos. Her case was brought with that of Lorraine Hadley, 37, from Sandwell, West Midlands, who has two embryos in storage created after IVF treatment with her former husband Wayne. As in Evans’s case, Hadley’s former husband later changed his mind, and said that he wanted the embryos destroyed.

The women were unsuccessful in their hearing before Mr Justice Wall and Hadley, who has an adult daughter from a previous relationship, chose not to appeal against the High Court’s judgment. For Evans, though, the embryos still in storage represent her last chance to have a child that would be genetically hers. The embryos of both women remain in storage pending the outcome of this week’s appeal.

Muiris Lyons, a partner at Withy King who is acting for Evans, says: “We accept that this case raises some very difficult issues. But the Court of Appeal has already recognised the substance of our arguments by giving Natallie permission to appeal.”

Evans’s case is based on a series of complex and interrelating legal arguments, at the core of which is a challenge to the Human Fertilisation and Embryology Act 1990. This requires the destruction of embryos unless both parties consent to storage and use, and says that either party may withdraw consent at any time until the embryos “are used in the provision of treatment services”. As Lyons says: “The issue at the heart of the case is that of consent and the extent to which it can be and has been withdrawn. The question is, at what point are the embryos used in the provision of treatment services?” Evans argues that “use in treatment services” does not simply mean implantation, but covers other aspects of the IVF process. She will claim that it is too late for Johnston to withdraw his consent because, technically, the embryos have already been “used” as part of her treatment. In addition, she will put forward the doctrine of equitable estoppel, saying that Johnston gave up his right to change his mind by promising her that she could use the embryos, a promise upon which she relied to her detriment.

Two other arguments will be advanced. Evans will claim that Johnston’s withdrawal of consent is an unnecessary interference with her right to a private and family life under Article 8 of the European Convention on Human Rights, and that the law grants Johnston a “male veto” over the use of her embryos, again contrary to the convention.

In effect, she is saying that in the ordinary course of events once a man has played his part he has no right to interfere when a woman becomes pregnant, but that the law in IVF cases is unfair and discriminates against sick, disabled and infertile women in breach of their right not to be discriminated against under Article 14.

In the High Court last year, Mr Justice Wall expressed his “considerable sympathy” for all concerned, particularly Natallie Evans. But the judge said that he could not allow his sympathy for Evans “to take precedence over the clear terms of the Act (which) entitles a man . . . to say that he does not want to become the father of a child by a woman from whom he has separated, and with whom he now no longer has anything in common apart from the frozen embryos”.

Until the outcome of the Court of Appeal case, Lyons is keeping his feet on the ground. “We hope that Natallie will be successful,” he says. “But I have a feeling that, whatever the result, the case will be appealed.”

Natallie Evans may have to take her case all the way to Europe but she will be hoping that the judgment of Solomon tips her way.