1 Instituto de Reproducción CEFER (CENTRO MEDICO TEKNON), Marquesa de Vilallonga 12, 08017 Barcelona and 2 Fundació Pro-Donació D'Òvuls, Spain
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Abstract |
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Key words: gamete donors/oocyte donation/ovum donation/screening oocyte donors/student oocyte donors
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Introduction |
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The increased demand for donated oocytes is a reality. In the UK, IVF cycles with donated oocytes have increased fivefold in 3 years (Human Fertilisation and Embryology Authority, HFEA, 1996). Our own experience corroborates this increase in oocyte demand, which has doubled in 3 years. However, another reality is the scarcity of donated oocytes (Brown, 1998). This parallel reality may explain the long waiting lists (taking years in many cases) and the fact that, in 1994, 35% of the centres practising assisted reproduction techniques in the USA did not offer oocyte donation programmes (Society for Assisted Reproductive Technology Registry, 1996
). In Spain, over 50% of assisted reproduction centres do not practice oocyte donation. The difficulty lies in obtaining donated oocytes. We present our centre's experience with donor recruitment, donor selection, and the results obtained.
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Materials and methods |
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Information
Briefly, the information given to suitable candidates was as follows:
Family medical history
The family medical history was taken on the donor's closest family members: her parents, brothers and sisters and children. Information was also gathered on her aunts and uncles, cousins, nephews and nieces, etc. The medical history included asking the potential donor whether any of her family members (especially first-degree family members) had suffered or suffer from epilepsy, schizophrenia, mental disorders, or mental deficiency, and whether there had been any cases of suicide in her family; congenital blindness or deafness, congenital defects of the heart, lungs, kidneys or spinal column (spina bifida), coagulopathy, type I diabetes, intestinal polyps, inherited hypercholesterolaemia, death from cancer (including type), early death from heart ailments (40 years of age), thyroid or growth pathologies, and any other illnesses in the candidate's family that she was aware of.
Personal medical history
The following aspects were considered with respect to the potential donor's personal medical history: previous allergies; eye, ear, liver, kidney, heart, lung, vertebral and neurological pathologies; previous injuries; surgical operations; hospital treatments; anaesthesia, and causes. Sexual aspects: whether the donor had a stable partner or not; whether she used contraceptives in the past and present. Reproductive aspects: previous pregnancies, miscarriages and legal interruptions of pregnancy; any children. Habits involving toxic substances: alcohol, tobacco and other drugs. No strict limits were applied about alcohol intake, cigarette smoking, or drug use. The recommendations were no more than 20 g of alcohol and/or 20 cigarettes per day, and no regular use of drugs. Sports: whether she played sports or not. Potential donors were asked why they wanted to donate their oocytes. Race, weight, size, and hair and eye colour were recorded. The acceptance study continued in those cases in which the family and personal medical histories did not reveal anything that impeded the candidate from donating her oocytes.
Examination
The gynaecological examination entailed the following: breast examination, body hair distribution, visceromegalies, external genitals, vagina, uterus and ovaries. A vaginal sample was taken for culture. In transvaginal ultrasonography, the following aspects were considered: (i) uterus: size, morphology, ultrasonographic pattern and position; endometrial cavity and appearance, and whether it was concordant or discordant depending on the cycle phase. Possible pathologies such as polyps, submucous myomas, haematometra or mucometra; (ii) ovary: structure, size, and position; (iii) uterine tubes: presence or absence of hydrosalpinx and hydatid of Morgagni. Ovarian accessibility for ovum retrieval by vaginal ultrasound was also evaluated.
Blood tests
Where there were no contraindications for accepting the candidate as a donor, blood tests were carried out, consisting of analysis for hepatitis B and C, syphilis, and acquired immune deficiency syndrome (AIDS); coagulation factor VIII, fetal haemoglobin and mitotic karyotype. No blood tests for ovarian activity were performed, since the donors were young and had regular menstrual periods. Neither were blood tests for Chlamydia or cystic fibrosis carried out because of the high costs involved. If the blood test results were normal, the candidate was accepted as a donor. All donors had to sign an informed consent form.
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Results |
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Discussion |
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The donor's liability with respect to the transmission of genetic or infectious diseases is a subject which is not addressed in the Spanish law. This liability lies with the medical team, which is required to comply with the legislation in force at the time. Besides taking the donor's medical history, it is compulsory to test for hepatitis B and C, syphilis and AIDS. If the donor knowingly hid any valid information that could cause a genetic or infectious disease to be transmitted to the mother or child, the donor would be liable. If the donor did not hide any information, the liability pertains to the doctor, and the risk is assumed by the recipient mother when she signs the informed consent form. Therefore, it is the doctor's responsibility to select the gamete donor correctly. The availability of a greater number of candidates would make it easier to select only the best ones, and would make rejection automatic in cases where there is doubt as to the suitability of the donor. However, if the number of potential candidates is low, the standards for acceptance are lower (Sauer and Paulson, 1992).
Oocyte donations are accepted from the following groups: (i) Donors brought by the recipient couple, their friends or family. In our opinion, this is not a valid solution to the problem, because it is obvious that the group of possible donors a sterile couple has access to is very limited. Furthermore, this system of donor recruitment does not allow the recipients to maintain their sterility problem and their decision to seek donated oocytes as private. The assisted reproduction centres that use this strategy force the recipient to find a suitable donor or give up the chances of having a child. The situation becomes worse if the recipient and the donor live far away from the assisted reproduction centre, or if pregnancy is not achieved after the first attempt. The Spanish law's requirement for anonymity between donor and recipient means that the oocytes of the donor brought by a specific recipient couple cannot be used by that couple and forces interchange of donors between couples. Moreover, particular ethical issues arise from this way of obtaining oocytes, as exemplified by a case witnessed by our team, where the recipient couple brought their domestic employee to act as donor. We find this option invalid and impractical. Given that it is now unthinkable to expect patients requiring a kidney, medulla, cornea or semen to find a suitable donor, why should the situation be different with respect to oocytes? (ii) Women who are going to have their Fallopian tubes tied. The main problem here is that such women are usually over 35 years of age, which is in itself sufficient reason to reject them. Our experience indicates that this group of potential donors is highly inadequate, and we gave up on this option several years ago. Other authors have published rather scant donation results from this group: of 194 women about to have tubal ligation, only 2.5% were accepted as donors (Feinman et al., 1989). (iii) Women undergoing in-vitro fertilization (IVF) to solve their own sterility problem, who share their oocytes with other women. This is a large, but sterile group. Their sterility is often due to genetic illness, and these women are close to or over 35 years on average. In the USA, 45% of assisted reproduction centres provide incentives for these women to share their oocytes (Braverman, 1993
). The most relevant problem we see in these cases is that the woman undergoing IVF reduces her own possibilities of becoming pregnant when she shares her oocytes. An infertile woman who wants to have children can never have too many oocytes. Oocytes for donation were obtained from women undergoing IVF who produced 10 or more oocytes (Remohí et al., 1993
). However, the chances of producing offspring are 28.3% when six to 10 mature oocytes are obtained, and 41.5% when >10 mature oocytes are obtained (Toner et al., 1993
). British Human Fertilisation and Embryology Authority (HFEA) data indicate that for every child born, 39.3 oocytes (of which 16.7 go unfertilized) and 22.6 embryos are required (HFEA, 1998, cited by Ahuja et al., 1998). In our experience, women do not usually accept sharing their oocytes even if the cost of IVF is reduced. Their main objective is to have children, not to save money. When patients cannot afford IVF privately, they go to Social Security centres, where such treatment is free, even though the waiting lists are fairly long. The solidarity of women undergoing IVF is manifested by the fact that they donate the embryos they are not going to use. However, in recent years, more women have preferred to have their embryos frozen rather than donate their oocytes (Quigley et al., 1991
). Until 1994, Rosenwaks and Damario obtained only 15% of their donations from this group, and they note a downward trend (Rosenwaks and Damario, 1996
). The waiting period for the recipient couple is extended to years with this method of obtaining oocytes. Ahuja et al. defend the concept of sharing oocytes. The group in their study (n = 114) presented with two characteristics worth highlighting: 41% had already had children and 30% were between 35 and 44 years old (Ahuja et al., 1998
). In Spain it is illegal for women over the age of 35 to donate oocytes. There is an increased risk of Down's syndrome and the fertility of these women, which is already low, is reduced even more if they share their ooctyes. It has also been stated that oocytes should be shared for financial reasons (Ahuja et al., 1998
). These authors argue that IVF is more effective because more children can be achieved by sharing gametes. Even if this were true, more children would be born, but not to the donor. These authors also point out the limited effectiveness of using frozen embryos to achieve pregnancies (somewhat more than 10% according to the 1997 HFEA data quoted by Ahuja et al., 1998). Our own experience shows that the pregnancy rate using frozen embryos is about 30% (data not published). Similar percentages have been published by other authors (Veeck et al., 1993
). It is our opinion that sharing oocytes reduces the patient-donor's own chances of having children. (iv) Women in general. A considerable problem in this case is that members of marginal sectors of the population may respond to such an advertisement. Some of the causes for exclusion seem to endorse this perspective: donors are not accepted if they have a low educational level, a history of sexual abuse or drug addiction, venereal disease, or multiple sexual partners (Gorril, 1998
). When one of the requirements is having a stable partner and children, the response is poor, as reflected by the fact that only 63 women were accepted in the UK after more than £30 000 was spent on an advertising campaign (McLaughlin et al., 1998
). (v) The student population. This is a large group of young women with a medium-to-high level of intelligence who have the time available for donation. It is not a marginal group. The fact that they are young means that the quality of their oocytes will be better, because it is known to decrease with age (Meldrum, 1993
). They do not strictly have to be between 18 and 25 years old. Spanish law states that donors can be as old as 35 years. Most university students are between 18 and 25 years. Our view is that younger women are more altruistic, have had fewer sexual partners, and have a lower risk of venereal disease. The fact that these candidates were young could also explain why 51% did not continue with the study. Many came for information because they were curious. With these donors, the waiting period for the recipient woman is reduced to a few months. According to our experience, the student receiving economic compensation is the most suitable donor and the one that recipients accept best. It has been stated that the word `donation' implies an altruistic act and precludes payment in its definition (Shenfield, 1998
). The HFEA is hesitant about paying semen donors; it is against the idea in principle, but admits that in practice, semen donors are given £15 per donation plus expenses. The amount paid to cover expenses is not specified. Is this purchase or compensation? The HFEA makes no reference to oocyte donors (Deech, 1998
).
It is a moot point whether oocyte donation is a sale, a donation that should involve compensation for the time and travelling required by the donation process, or a truly altruistic act. In Spain, despite ongoing controversy, remunerating the donor to compensate for the time taken and the travelling involved is accepted. Donors could not possibly be expected to invest their own money in order to donate oocytes. The Ethics Committee of the American Fertility Society (1994a), the Council of Europe Document on Human Artificial Procreation (CEDHAP, cited by Gorril, 1998), the HFEA (1997) and even the French federation CECOS (Guerin, 1998) accept the idea of giving economic compensation for gamete donation. It is also worth mentioning that the five donor groups mentioned above actually receive compensation in one way or another: (i) Donors brought by the recipient couple are said to be altruistic, but that may be because the doctor is unaware of the compensation agreed upon between the donor and the recipient couple, even when the former is a family member. Gratitude is human and understandable. For instance, we experienced a case where a recipient woman paid for the shoes and school books of her sister's three children in exchange for her acting as a donor. The pressure placed on the family member by the recipient woman has been mentioned (McLaughlin et al., 1998
). (ii) Donor women who are about to have tubal ligation receive this treatment free of charge, and at public institutions they are given priority over other women on the waiting list. Thus, they also receive a kind of compensation. (iii) Women who share their oocytes are also charged less for the assisted reproduction services they receive, or are given priority over other people on the waiting list at public centres, and this can be seen as compensation of a kind. It is very unusual for a woman undergoing IVF in a private assisted reproduction centre to share her oocytes without receiving compensation, unless she has not been clearly informed about how her own chance of becoming pregnant and having a second child are reduced. The idea that she might not become pregnant while the woman who receives her oocytes succeeds in having a child can be horrifying. The percentage of women undergoing IVF who also donated some of their oocytes and became pregnant was 20%, compared to 30% of recipient women who became pregnant (Ahuja et al., 1996
). (iv) For women in general, the economic compensation for oocyte donation can be very high: up to 2900 euros (Braverman, 1993
), even when an agency acts as the intermediary in the donation process (Seibel and Kiessling, 1993
). According to the CEDHAP, agencies offering gametes should not be allowed to make a profit. The economic incentive could lead candidates to conceal important health information, and could make the process more expensive for the recipient. Women from the lowest social classes might attempt to make money with their oocytes. (v) The amount received by students, about 750 euros, covers the time and travel expenses involved in oocyte donation (it may be necessary to make up to 20 visits to the clinic). When altruistic volunteers do not end up donating it is usually because of the distance from their home to the clinic, time commitments, or work commitments (Kan et al., 1998
). Compensation attempts to overcome these objections. The inconveniences and risks involved in donation are difficult to quantify. From our point of view, this demonstrates the student's altruism when becoming a donor. For the cases of donor recruitment presented in this article, selection and compensation were carried out by the Fundació pro-Donació d'Òvuls, a non-profit organization. Naturally, the amount paid to donors does not depend on the number of oocytes obtained.
Where is the borderline between purchase and compensation? We believe there are two points to be considered: (i) the amount received, i.e. whether the amount given to the donor is evaluated as a function of the number of hours involved and the travelling required for the donation. The amount of money that person could have earned if she had been working is therefore taken into account; (ii) whether there is a relationship between the number of oocytes obtained and the amount received. In this second case, one could speak of the purchase of oocytes at so much per unit. The student's reason for donating her oocytes and how she will use the money she receives is considered to be irrelevant. Since the candidates are university students, they belong to upper- or middle-class families. They do not have urgent economic needs. In fact, 253 out of 554 (45.6%) abandoned the treatment even though they were aware of the economic compensation.
Oocyte donation involves inconveniences such as hormone injections, blood tests, vaginal ultrasonography, and a possible sensation of swelling in the lower abdomen caused by follicle growth. Oestrogen deprivation from GnRHa administration and the reaction against gonadotrophin impurities does not apply to our donors because a short stimulation cycle is used, and the FSH is either pure or recombinant. The risks involved in oocyte donation are those inherent in ovarian stimulation and follicular puncture.
All of the donor groups mentioned above, except for those participating in IVF for their own sake, must assume the risk of ovarian stimulation. This has been used as an argument to defend the idea that only oocyte sharers should be allowed to donate oocytes (Ahuja et al., 1999). In the groups of donors who are not patients, the risk of hyperstimulation is lower than it is for IVF patients because the donors will not receive the embryos, i.e. they will not become pregnant (Sauer and Paulson, 1994
; Morris, 1998
). This fact is not mentioned by Ahuja et al. (1999).
There have been no unplanned pregnancies among our donors. Other teams have published results showing up to 7% unplanned pregnancies among oocyte donors during donation cycles (Sauer and Paulson, 1994). Some prudent measures to be taken in donor stimulation to further reduce the risk of hyperstimulation are as follows: follicle puncture should be performed on both large and small follicles; albumin should be administered intravenously during oocyte retrieval, and HCG should not be administered when there is a clear risk of hyperstimulation. After handling over 200 donors, we have not experienced any serious cases of ovarian hyperstimulation.
The increased risk of ovarian cancer due to ovarian stimulation has not been proven (Rossing et al., 1994), especially in those cases where the mother did not suffer from ovarian cancer (Whittenmore et al., 1992
). We believe it is important to continue monitoring non-patient donors, but at present, the risk of ovarian cancer as a direct result of gonadotrophic treatment cannot be denied, affirmed, or quantified.
There are three main risks resulting from follicular puncture: the anaesthetic, pelvic inflammatory disease (PID), and haemorrhage. These are risks that donors would not be subjected to if they were not donating their oocytes. The risk of PID has been associated with a history of previous PID (Yuzpe et al., 1989; Dicker et al., 1993
). Other factors to be considered are antibiotic prophylaxis and vaginal antisepsis. The incidence of PID as observed in two large series is about 0.6% (Bennett et al., 1993
; Ashkenazi et al., 1994
). Student donors who have not previously suffered from PID, whose cervixvaginal secretion culture results are negative and who have received antibiotic prophylaxis have an even lower risk of contracting PID. In our experience, only one woman out of 201 (0.5%) suffered from such an infection. The case for possible future sterility caused by PID after follicular puncture is insufficiently documented. In 26 laparoscopic evaluations performed after follicular aspiration, no adnexal adhesions were observed (Amso, 1995
). Considerable haemorrhage following oocyte retrieval occurs in 0.40.8% of cases (Bennett et al., 1993
; Ashkenazi et al., 1994
). Of the donors in our study, there was only one case of haemorrhage (0.5%), which required laparoscopic exploration but had no further consequences. The risks caused by propofol anaesthesia controlled by an experienced anaesthetist are very low. We believe that non-patient donors can safely assume the risks inherent to oocyte donation. Ahuja et al. are of the opinion that sharing oocytes allows the recipient to seek treatment in a decent way, without having to resort to offensive advertisements (Ahuja et al., 1999
). The signs we post on university bulletin boards read as follows: `You are a source of life. Donate your ovules. Students wanted as donors. The ovules will be used exclusively to help infertile couples. Economic compensation: 750 euros'. We do not find this advertisement offensive.
The methodology used in the process of donor selection allows for a high degree of safety with respect to the transmission of infectious illnesses to the recipient. The group chosen is young and not marginal, thus implying a shorter history of sexual intercourse and fewer sexual partners, which in turn lowers the risk of acquiring infectious diseases. None of our donors had suffered from any sexually transmitted diseases in the past. It seems unlikely that the oocyte could be a carrier of infection.
Genetic diseases, however, cannot be completely ruled out. All the blood tests that are compulsory in Spain, as well as those recommended by the Ethics Committee of the American Fertility Society (1994b) were carried out. The availability of a large group of donors facilitates rejection in doubtful cases or when genetic diseases are suspected. Specific analysis to detect the most common genetic pathologies in our population, such as haemophilia A and ß thalassaemia further reduce the risk of genetic transmission of the disease to the fetus. The economic cost is a factor that limits more extensive genetic testing. One of the axioms we have learned after more than 20 years of experience with semen donor selection from university students has been applied to oocyte donors: have a large number of candidates so that doubtful cases can be rejected. Karyotype studies are only required in 14% of assisted reproduction centres in the USA (Gorril, 1998). However, in our group of student donors without children, we felt it necessary to carry out karyotype analysis. In three cases out of 227 (1.3%), we found chromosome disorders that could have resulted in miscarriage or fetal deformities. The recipient women may consequently be able to avoid amniocentesis because the oocytes come from young women with a normal karyotype.
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Conclusions |
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Acknowledgments |
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Notes |
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References |
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Submitted on April 6, 1999; accepted on August 5, 1999.