Letter: Number of eggs is hard one to crack

YOUR REPORT "Two egg limit for fertility women" (12 December) implies there is general accord among fertility specialists in agreeing with Allan Templeton's edict that only the best one, or two, embryos should be implanted with IVF, to minimise the sequelae of multiple births. This is far from the case. Professor Templeton, using the database of the Human Fertilisation and Embryology Authority (HFEA), distorts the true picture for medico-political reasons. We all share concerns about the consequences of multiple births, but our clinical duty is to maximise the prospect of pregnancy for an individual infertile couple and minimise the risk of a multiple birth.

To impose a fixed upper limit of two embryos for all women is to deny those with less favourable features the chance of having their own biological child. Since 1987 licensing authorities, by limiting the maximum of three embryos to all, have prevented many women from conceiving. We have evidence of this by transferring more than three eggs with sperm into the Fallopian tube in women aged 40 and over, using the GIFT technique, and have doubled the pregnancy outcome without any triplets occurring. Inferring that all women have the same fertility potential and risk of multiple pregnancy is biologically inaccurate.

What we require is flexibility so that it is possible to select an appropriate number of embryos for transfer in different individuals with different fertility prospects. Some will need only one or two embryos and others three or more to maximise their chances of having a singleton child.

We certainly do not want rigid rules and potential legislation that will damn the least favourable.

Professor IAN CRAFT

London Fertility Centre

London W1