A woman undergoing IVF treatment who was dismissed three days before her fertilised eggs were implanted was not pregnant according to European law, European Union judges ruled today.

The distinction is crucial for Sabine Mayr, an Austrian waitress fighting an unfair dismissal case in a Salzburg court, who claims she was pregnant from the date of fertilisation, not implantation.

If she wa right that would mean she was protected against dismissal under Austria’s laws on maternity protection.

But the European Court of Justice - asked by the Salzburg court to clear up the confusion - decided today that “for reasons connected with the principle of legal certainty”, Ms Mayr could not be deemed to be pregnant before implantation.

“The protection against dismissal established by the (EU) Directive on the safety and health at work of pregnant workers cannot be extended to a pregnant worker where, on the date she is given notice of her dismissal, the ’in vitro’ fertilised ova have not yet been transferred into her uterus,” judges at the European Court of Justice said.

If a woman were deemed pregnant at that point, the judges argued, that would offer legal protection on maternity grounds to women who may then postpone implantation for any reason, or abandon it altogether.

However, Ms Mayr may still be entitled to some protection because the judges said she could be covered by EU anti-discrimination and equal treatment laws.

“Treatment such as that which Ms Mayr has undergone directly affects only women,” they said. “The dismissal of a worker essentially because she is undergoing a transfer of fertilised ova into her uterus therefore constitutes direct discrimination on grounds of sex.”

The judges said that it was now up to the national court to establish that Ms Mayr’s dismissal was actually linked to the fact that she was undergoing IVF treatment at the time.

But lawyers said the ruling would have direct ramifications for the UK.

Rachel Dineley, an employment partner and discrimination specialist at law firm Beachcroft, said: "IVF is now much more common (with an estimated 1 in 7 women finding difficulty in conceiving) and employers need to make sure they have appropriate policies in place.

"The ECJ has made clear that IVF treatment is likely to fall within the Equal Treatment Directive, even if the employee is not yet technically pregnant. This means that employers should take a supportive approach to women who are undergoing IVF treatment.

"To subject a woman to any form of detriment as a result of her having treatment at the very least risks a claim under the Sex Discrimination Act," she said.

Martin Warren, head of employment law at Eversheds law firm, said: “The central concern of most employers in relation to this issue is how they might manage an employee’s pattern of absence during IVF treatment. Previously, this may have led some employers to discipline or even dismiss a woman undergoing treatment but this ruling clarifies that this could now be considered an unlawful and potentially highly costly course of action.”

“Practically speaking, it is important for employers to act on facts rather than assumptions when dealing with employees undergoing the treatment. Preserving confidentiality, having an audit trail and giving the employee the chance to explain the consequences that the treatment will have on her attendance, can help to minimise the likelihood of a claim,” he said.

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