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Where am I now? Lawlink > Law Reform Commission > Publications > Chapter 10 - Limitations on Use of Donor Semen
Discussion Paper 11 (1984) - Artificial Conception: Human Artificial Insemination
Chapter 10 - Limitations on Use of Donor Semen
I. ACCIDENTAL INCEST
10.1 A matter of recurrent concern in both the literature and public discussion on AID is the possibility that AID children conceived from the sperm of one donor might, without knowledge of their relationship, marry and have children. The husband and wife would be half-brother and half-sister. The concern is a reflection of the historic social taboo against inbreeding. One rationale for the taboo is that the rate of mortality and malformation in newborn children increases as the blood relationship between the parents becomes closer. The progeny of first cousins show a rate that is higher than normal, and it is likely that the children of half-brother and half-sister would be at an even greater disadvantage.1
10.2 Expressions commonly used to describe this possibility include “consanguineous marriage”, “innocent consanguineous marriage”, “accidental incest”, “half- sib mating”, and “inadvertent inbreeding”.
10.3 This subject, of its nature, tends itself to conjecture and attracts the attention of the news media, no doubt because of the absence of factual evidence of any such mismating (our research has disclosed no recorded case) on the one hand, and the theoretical possibilities on the other. We do not, however, dismiss this concern, or discount its significance, because our inquiries into AID practice in New South Wales have shown that clinics, almost without exception, control very carefully the number of inseminations performed with the sperm of one donor. Accordingly, we list in the next paragraph some of the relevant scientific Ind medical propositions put forward by recognised experts.
II. STATISTICAL INFORMATION
10.4
For a city the size of Sydney... the probabilities of a CM (consanguineous marriage) for four or two recipients are...... about 1 in 60,000 and 1 in 115,000 respectively. The probability of a CM for six recipients is... 1.4 times greater than... four (ie. 1 in 40,000).2
[A]pproximately 3% of all babies born have some serious abnormality. [What is the maximum acceptable risk of additional abnormal offspring due to half sibling matings resulting from AID? The choice of this figure is arbitrary.] A figure of 0.1% would probably be acceptable... However, calculations show that the risk is most unlikely to approach even this figure.3
... A certain number of half-sibling marriages must take place unwittingly anyway, as a consequence of extra-marital conceptions and the increase in their number due to AID would be expected to be very small, provided that the number of babies fathered by a single donor remained small ... the highest recorded number of live births from one donor is 17-1 most doctors set a limit at four or five. Glass has estimated that, if 2,000 live children a year were to be born in Great Britain as a result of the successful use of AID, and if each donor were responsible for five children, an unwitting incestuous marriage is unlikely to take place more than once in 50-100 years.4
Consideration should be given to limiting the number of pregnancies from any one donor (e.g. up to 20).5
So not only then is the risk of consanguineous marriage of AID offspring extremely small but it probably also is insignificant in proportion to the problems attributable to irregular unions, at least in London.6
Inbreeding will not be a problem unless the numbers are very large. It is a good idea to limit donors to, say 20 or so donations - something that is easily achieved.7
There are, perhaps, 10,000 children delivered annually in the United States as a result of AID. This is compared with a total birth number of over 300 times that. Allowing for the mobility of our population, marriages to foreign-born people, and the huge age-spread often seen between husband and wife, one can say that the risk of consanguinity is very low.8
[M]ating within one’s community will increase this risk I of inbreeding] ... a single donor may make a large contribution to a local ethnic community. Intra-marriage within such a community would result in increased inbreeding due to artificial insemination In fact, several half-sib matings have nearly occurred already, and our data further suggest that inbreeding may be more frequent than expected. The probability of consanguinity between donor and recipient may also be increased since donors have the same approximate age and socioeconomic background as recipients.9
10.5 In his analysis of the subject, Danks considers not only the population of the particular community (e.g. the State of Victoria) but “the size of the effective breeding population to which the donor and the recipient belong.10 He continues, “One must at least restrict this to the age group of the donor - perhaps 5 years above or below his own age... We then come to ethnic subdivisions of the community which do not interbreed very freely and to social subcategories within these”. Danks produces a table expressing in percentage terms the likelihood of unwitting half- sibling mating from AID inbreeding pools” of various sizes. The likelihood in all cases is low.11
III. PRECAUTIONS TAKEN
10.6 We have made specific inquiries of all known AID practitioners and clinics in New South Wales, and have found that, with one exception, they all consciously apply a deliberate limit to the quantity of semen used from one donor. The limits of usage are expressed not so much by restricting the absolute number of inseminations as by monitoring the number of pregnancies (in most cases) or live births (in some cases) resulting from one donor. It is plain that if the objective is to reduce the possibility of innocent consanguineous mating, the determining factor should be the number of babies born from the sperm of one donor. Once a decision is made on the critical number, its achievement should be followed by cessation of use of that donor’s semen in AID. From a practical point of view this is easier said than done, because it is possible in theory to carry out a great number of inseminations with one donor’s sperm long before his first AID child is born let alone the fourth or fifth, or whatever number is chosen. The only practicable approach (which is followed by most clinics) is to impose a temporary limit upon the number of women inseminated with a donor’s sperm, and then to suspend usage of his sperm pending results. If pregnancies do not result, usage may be recommended. If pregnancies do result, usage may remain suspended until the outcome of the pregnancy is known. In this way sensible control is exercised.
10.7 We have been impressed by the care taken by clinics in New South Wales on this subject. Seven clinics informed us that they observed a systematic policy of limitation upon the use of the sperm of a donor in AID. The limitations were described as follows:
- limit of four or five pregnancies;
- limit of four pregnancies within Sydney Metropolitan Area;
- limit of six pregnancies excluding donor’s children by his marriage;
- limit of three pregnancies;
- limit of five live births;
- limit of four live births; or
- limit of 16 inseminated women per donor.
The clinics agree that it is possible for a donor to confuse them by giving false information about prior donations at other clinics but most expressed the view that this is unlikely to occur. The reason is that donors are usually actively sought by clinics, and are usually carefully and thoroughly interviewed before acceptance. With some clinics donors are usually medical students working in that department of the hospital for only one year of their studies. The main categories of donors, according to our information are four, namely medical students, hospital workers, husbands of gynaecological or obstetric patients who have been successfully treated for other problems, and persons responding to advertisements in the press or in blood banks or to word-of-mouth request.
10.8 One clinic informed us that it takes special care with AID recipients who live in country towns or other identifiable areas away from Sydney. The clinic considers the size of the local population and other considerations of a more personal nature, for example, the racial background of the recipient, and applies much more stringent limitations to the use of the sperm of individual donors for such patients than for patients living say, in Sydney.
IV. OUR APPROACH
10.9 It seems fair to conclude that the likelihood of innocent consanguineous mating in New South Wales between AID children, is low mathematically (see paragraph 10-4). We acknowledge that the general proposition will not apply in all cases and that there will be particular circumstances when the likelihood of inbreeding will be higher (even much higher).12 We have noted that, generally speaking, the medical profession in New South Wales has already taken careful steps to establish routine procedures that are designed to keep the prospects of inbreeding at a low level. Once again, as with other procedures referred to in Chapters 7 and 8, the procedures vary from clinic to clinic (see paragraph 10.7). Further, it is clear that not every medical practitioner uses the same numerical limitation.
10.10 We tend to favour the view that direct legal intervention is unlikely to achieve a better result than has already been achieved by the medical profession acting within its own ethical and practical standards. Yet guidelines could well be useful, to provide clear pointers to the ‘iterations that should govern decisions on the continued use of a donor’s sperm. We have no concluded view whether the production of guidelines should be left solely to the medical profession or whether legislation should make some contribution. This could take the form, for example, of a general statutory statement requiring AID practitioners to have regard to the question of consanguineous mating prior to inseminating a patient.
10.11 The necessary considerations are well described by Danks, whose summary also provides the argument for conferring a discretion on the person making the decision:
Those determining the policies of AID clinics must make their own decisions regarding the likely size of the defective breeding pool in the population with which they are dealing. It is clearly important to look at this problem realistically when dealing with different ethnic groups and to have a flexible policy rather than just one fixed policy for all groups in the population- It would be undesirable to allow more than one AID offspring per donor in a very small ethnic group; however, considerable numbers might be allowed in the Anglo-Saxon Australian population. The more socially and geographically mobile the donor and recipient the less the risk. There is also some conflict between the desire to choose a donor from the same ethnic group as the recipient when dealing with small ethnic groups.13
V. ISSUES FOR REFORM
10.12 (1) Should the risk of innocent consanguineous mating between half-siblings born as a result of AID be considered by AID practitioners in relation to the frequency of usage of the semen of one donor?
(2) If so, should the law intervene with specific criteria to be observed in all cases?
(3) Instead of legal intervention should the prescription of procedures be left to the medical profession?
(4) If the answer to (3) is yes, should the medical profession be left to develop procedures as it determines or should the law establish general guidelines?
(5) In relation to both (2) and (3) is it desirable to envisage legal sanctions or punishment?
Footnotes
1. Ciba Foundation Symposium 17, Law, and Ethics of ALD. and Embryo Transfer (1973), p.7.
2. J. A. Eccleston, “The Probabilitv of a Consanguineous Marriage Occurring is a Result of Artificial Insemination” (1978) 5(i) The Australian Mathematical Society Gazette 90, at p.91.
3. C. Wood et al. (eds.), Artificial Insemination by Donor (1982), p.101.
4. See note 1 above, p.7.
5. Royal College of Obstetricians and Gynaecologists, Recommendations for Centres Planning to set up an AID Service, p.2.
6. Royal College of Obstetricians and Gynaecologists, Artificial Insemination (1976). p.66.
7. Id., p.72.
8. S.L. Corson et a1., “Donor Insemination” (1981) 12 Obstetrics and Gynaecological Annua1 28 at p.289.
9. M Curie-Cohen et al., “Current Practice of Artificial Insemination by Donor in the United States” 300 New England Journal of Medicine 585, at p.589.
10. See note 3 above, p.101.
11. Id., p.102. table 1.
12. See paras.10.4, 10.5, and 10.8.
13. See note 3 above, p.102.
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