Report of the Committee of Inquiry into Human Fertilisation and Embryology / Chairman: Dame Mary Warnock, DBE.

  • Great Britain. Committee of Inquiry into Human Fertilisation and Embryology.
Date:
1984
Catalogue details

Licence: Open Government Licence

Credit: Report of the Committee of Inquiry into Human Fertilisation and Embryology / Chairman: Dame Mary Warnock, DBE. Source: Wellcome Collection.

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    of time for which an embryo can be kept alive in vitro. While, as we have seen, the timing of the different stages of develop- ment is critical, once the process has begun, there is no particu- lar part of the developmental process that is more important than another; all are part of a continuous process, and unless each stage takes place normally, at the correct time, and in the correct sequence, further development will cease. Thus bio- logically there is no one single identifiable stage in the develop- ment of the embryo beyond which the im vitro embryo should not be kept alive. However we agreed that this was an area in which some precise decision must be taken, in order to allay public anxiety. 11.20 The evidence showed a wide range of opinion on this question. One argument put forward may be termed the strictly utilitarian view. This suggests that the ethics of experiments on embryos must be determined by the balance of benefit over harm, or pleasure over pain. Therefore, as long as the embryo is incapable of feeling pain, it is argued that its treatment does not weigh in the balance. According to this argument the time limit for 12 vitro development, and for research on the embryo, could be set either when the first beginnings of the central nervous system can be identified, or when functional activity first occurs. If the former is chosen, this would imply a limit of twenty-two to twenty-three days after fertilisation, when the neural tube begins to close. As to the latter, in the present state of knowledge the onset of central nervous system func- tional activity could not be used to define accurately the limit to research, because the timing is not known; however, it is generally thought to be considerably later in pregnancy. With either limit, proponents suggest subtracting a few days in order that there would be no possibility of the embryo feeling pain. 11.21 The Royal College of Obstetricians and Gynaecolo- gists suggested that embryos should not be allowed to develop in vitro beyond a limit of seventeen days, as this is the point at which early neural development begins. The British Medical Association favoured a limit of fourteen days and a number of groups, including the Medical Research Council and the Royal College of Physicians suggested that the limit should be at the end of the implantation stage. Again, some groups submitting evidence suggested that no embryo which had gone beyond the beginning of the implantation stage should be used for research.