It is easy to underestimate the lengths to which some people will go to have children using the treatment services of fertility clinics. In extreme cases there is manipulation and also pressure exerted by patients over their partners, to which some clinics turn a blind eye. Counselling arrangements are often inadequate. Expert legal advice is rarely obtained. Fortunately, the law, which has retained (at least for now) the fundamental ingredient of informed consent, actually deters individuals with fertility problems who will begin a relationship for the sole and, initially hidden, purpose of using the gametes of their partner in fertility treatment. The consent rule is a vital safety valve.

In a case where a woman dupes her partner and ends the relationship soon after the embryo is produced using the woman’s egg and his sperm, the man would not have any say over how the embryo is used, if the ruling had gone Natallie Evans’s way. He would probably not have been able to stop the implantation of the embryo. In these sorts of cases, little, if any, thought is given to the consequences of the breakdown in the relationship; the priority is to have the child, whatever the consequences, whatever the risks. There is, of course, no suggestion that Natallie Evans or her former partner deceived the other.

Evans was, however, under a fundamental misapprehension. Her assurance, which she relied on in court, not to seek any financial contribution from Howard Johnston was well meant but unenforceable. Such an undertaking would not be binding on anyone as it is not possible to oust the jurisdiction of the English court on the question of financial support for children. The welfare of the child, including his or her financial welfare, remains paramount. A mother after IVF treatment may be financially self-supporting at the time she gives birth, but what if she loses her job, or falls ill, or becomes permanently disabled and has no independent resources? The court in those circumstances would ensure that financial support is the responsibility of the legal father, whatever the assurances the mother has given earlier on that he will not have to pay a penny. And the claims could be substantial. In a case where the father is wealthy, it is not just the capped child support through the Child Support Agency that will be due. In many cases, there is further substantial maintenance and school fees to be paid on top, to reflect the reasonable needs of the child.

The judgment also briefly touched on Evans’s confirmation that she intended to carry the child herself and not engage the services of a surrogate mother. Here lies another potential pitfall. The withdrawal of the requirement for bilateral consent all the way through to implantation would inevitably lead to intractable disputes with the woman, or the man, claiming the right to have the embryo carried in the uterus of a surrogate mother irrespective of the wishes of the other party.

That would be going a step too far. The loss of control just might deter some from undergoing IVF treatment at all.

The author is a partner in the family law department at the City firm Withers LLP

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