Sir, - Dr Robert Doyle (November 9th) asks me to give scientific evidence on when I assume life to begin. The short answer is that I do not know when individual life begins and I do not think that scientific evidence can be used to prove when it does in fact start. This may explain why there has been so much debate for so long on the subject.
However, I do not believe that life starts at the moment of fertilisation. Apart from the question of uniovular twins, there is also the fact that in more than 50 per cent of cases where pregnancy has been confirmed by a biochemical test no viable baby will be produced. In addition, an unknown, probably very large, number of fertilised eggs fail to implant. I find it difficult to accept that these were all human beings.
The practical point of all this is that those who wish to legislate on the basis of life starting at conception would automatically outlaw the IUD and the "morning after" pill. Is it just that, quite apart from their right of conscience, women should be deprived of these options on the basis of what I consider to be a suspect definition of when life begins? - Yours, etc.,
Dr Conor Carr, Mount Pleasant Avenue, Ballinasloe, Co Galway.