The ECJ held that the purpose of the Pregnant Workers' Directive was to protect the health and safety at work of pregnant women and those who have recently given birth. It cannot therefore protect a woman in circumstances where, albeit in-vitro fertilised ova were actually in existence, they had not yet been transferred into her uterus.
However, the Equal Treatment Directive (76/207) would protect a woman at such an advanced stage of IVF treatment as existed in this case, if it can be established that the reason for her dismissal is the fact she has undergone such treatment. This is because this stage of the treatment, like pregnancy, affects only women and so dismissal for it would amount to direct sex discrimination (see notes at Pregnancy/dismissal or detriment for reason connected with and on Webb v Emo Air Cargo (UK) Ltd 1995 ICR 1021, HL).
For relevant general notes go to Illness, sickness and accidents/pregnancy related illness and/or emplaw web-updater notes on Sahota v Home Office and Pipkin, EAT on 15th December 2009.