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6. Ethical issues related to multiple pregnancies in medically assisted procreation.

In this sixth statement of the ESHRE Task Force on Ethics and Law, the focus is on the ethical issues raised by multiple pregnancies resulting iatrogenically from the use of medically assisted procreation. The incidence of multiple pregnancies and the consequences for the child are discussed, together with general and specific ethical issues. Four recommendations are made-single embryo transfer, public funding for assisted reproduction, multiple pregnancies reported as complications not successes, and a uniform method of presenting results.

Bioethical Issues↗

Safety issues in assisted reproduction technology: should ICSI patients have genetic testing before treatment? A practical proposition to help patient information.

ICSI is a highly efficient treatment of male factor infertility and therefore increasingly used to treat infertile men successfully. However, when used to treat patients with a genetic cause for their infertility, there may be an increased risk for the offspring. Chromosome aberrations, Y chromosome microdeletions and CFTR (cystic fibrosis transmembrane conductance regulator) mutations alone may explain up to 25% of azoospermia and severe oligozoospermia. These genetic defects could be identified before treatment, in which case informed decisions could be made by the couple to be treated concerning the treatment, prenatal testing or preimplantation genetic diagnosis. Therefore, we propose that men with very low sperm counts (<5 x 10(6)/ml) considering ICSI should always be informed of the possibility of genetic testing. The information should include a precise statement of the implications of the results for the patient, his family and his offspring, and reassurance that a decision to test or not to test, or the subsequent test results will not be used as a reason for withholding treatment. Testing should always remain voluntary, and the couples themselves should decide whether or not they choose to be tested. If an abnormality is identified, patients should be referred to specialist genetic counselling.

Chromosome Aberrations↗

Italy enacts new law on medically assisted reproduction.

In 2004, the Italian Parliament enacted a law regulating medically assisted reproduction. Although the law recognizes as legal certain assisted reproduction techniques, several other procedures are implicitly or expressly banned: oocyte and sperm donation, using embryos for the scientific research purposes and reproductive cloning. In this article, I outline the new legal framework, pointing out some of the shortcomings of its provisions, such as the failure to define what an 'embryo' is, the contradictions between this law and the law on abortion, the opportunity for Italian couples to circumvent some of the prohibitions by resorting to 'reproductive tourism', and the central role that physicians play in the new legal framework.

Cryopreservation↗

ESHRE Task Force on Ethics and Law 10: surrogacy.

This 10th statement of the Task Force on Ethics and Law considers ethical questions specific to varied surrogacy arrangements. Surrogacy is especially complex as the interests of the intended parents, the surrogate, and the future child may differ. It is concluded that surrogacy is an acceptable method of assisted reproductive technology of the last resort for specific medical indications, for which only reimbursement of reasonable expenses is allowed.

Advisory Committees↗

Ethics and reproductive medicine.

This article surveys relevant moral and ethical implications of reproductive medicine, excluding any aspects of contraception. To maintain the methodological priority of a moral perspective, it focuses on moral theory and ethics in general before looking at the impact of ethics on the different techniques applied in reproductive medicine. We suggest that discourse ethics should be centre-stage among the moral perspectives, since it has a unique capacity to synthesize, gauge and emulate other moral perspectives without necessarily replacing them. Questions of spousal fidelity, parental identity, sexual relations, reshaping of family ties, preimplantation diagnosis, discarding of human life, up to the question of what kind of life is generally acknowledged as worth living, and which is not, all these are morally significant topics. As well as providing a description of the techniques used in reproductive medicine, our article presents a rationale for charting potentials for moral problems. This renders it possible to elucidate the moral costs of each of the options offered by reproductive medicine in the light of whatever moral view one identifies with.

Cryopreservation↗

Perspectives in human reproduction.

In-vitro fertilization and embryo transfer represent only one of the rapidly emerging applied advances in reproductive medicine beginning in the late 1950s; these include 'the pill' and the IUD for contraception, and hormones for the infertile requiring gonadal stimulation by gonadotrophins, clomiphene citrate or bromocryptine, to mention but a few. But from where and when did the biological basis for these sweeping changes derive? Virtually all the recent applications grew out of imaginative basic research. Fundamental animal studies by pioneers, such as Chang, Thibault and Edwards, taught us nature's axioms for gametogenesis, fertilization, development and differentiation. Millions are now seeking voluntary manipulation of their intrinsic reproductive capabilities to gain quality of life benefits for themselves and their children. Although not universal, the popularity of such options sparked industrial investment, governmental policies and international agencies to promote development of safer, more effective drugs and devices. Increased advocacy of aggressive treatment for infertile couples was a spontaneous outgrowth of this movement. Thus, the right of individuals to procreate, even to pursue the extraordinary means required, arose from the diverse events of the nascent reproductive revolution.

Biomedical Research↗

Counselling and selection of homosexual couples in fertility treatment.

Artificial insemination with anonymous donor sperm (AID) is a widespread practice for heterosexual couples in which the male partner appears to be infertile. The Centre for Reproductive Medicine of the Brussels University teaching hospital has been one of the first to extend this form of therapy to lesbian couples. In the course of the past 7 years, 27 lesbian couples have come to the centre with a request for AID. The question of whether children can be brought up within such a frame of reference cannot be dissociated from the question of attitudes towards homosexuality as such. Such attitudes still solicit a whole range of controversial reactions. This paper will deal with the most important findings from investigations thus far carried out on the issue of homosexual parenthood. It also sets out the selection criteria used in the evaluation of applicants. A profile of the homosexual couples selected will be presented, with particular attention to their social status, their psychosexual development and their motivation towards parenthood.

Counseling↗

Medicolegal and ethical issues of cloning: do we need to think again and again?

Research on the cloning of human cells holds the promise of medical benefits, but cloning humans is a far more complex and ethically disturbing issue. Some have argued strenuously that human cloning should be banned permanently. They have called it immoral, repugnant, and abhorrent. Most European countries have already banned it, and others are considering a proscription. While allowing fundamental research in the field to progress, we need a wide debate on human cloning. We need to think about what, if any, circumstances might warrant cloning, as well as the circumstances under which it should never be allowed.

Bioethical Issues↗

Frequency-dependent selection, beneficial mutations, and the evolution of sex.

This paper presents a mathematical model of a population in which multiple alleles at a particular locus are maintained by frequency-dependent selection. The results suggest that, if the population reproduces sexually, the benefit conferred on the population by beneficial mutations at other loci will typically be much larger than if the population reproduces by asexual means. In part, this is true because, in asexual populations, beneficial mutations can produce suboptimal distributions of the alleles that are subject to frequency-dependent selection. Another factor that produces an advantage for sex is that, in asexual populations, beneficial mutations that have achieved a high copy number may nevertheless be lost from the population. This is highly unlikely in sexual populations.

Animals↗

Simulated ecology-driven sympatric speciation.

We introduce a multilocus genetically acquired phenotype, submitted to mutations and with selective value, in an age-structured model for biological aging. This phenotype describes a single-trait effect of the environment on an individual, and we study the resulting distribution of this trait among the population. In particular, our simulations show that the appearance of a double phenotypic attractor in the ecology induces the emergence of a stable polymorphism, as observed in the Galapagos finches. In the presence of this polymorphism, the simulations generate short-term speciation, when mating preferences are also allowed to suffer mutations and acquire selective value.

Animals↗

Antisense inhibition of flavonoid biosynthesis in petunia anthers results in male sterility.

Inhibition of flower pigmentation in transgenic petunia plants was previously accomplished by expressing an antisense chalcone synthase (chs) gene under the control of the cauliflower mosaic virus (CaMV) 35S promoter. This chimeric gene was not effective in inhibiting pigmentation in anthers, presumably because the viral CaMV 35S promoter was insufficiently expressed in cell types of this organ in which the pigments are produced. Insertion of the anther box, a homologous sequence found in other genes expressed in anthers, resulted in a modified expression pattern driven by this promoter, as monitored by the beta-glucuronidase (gus) gene. In addition to the basic CaMV 35S expression pattern in anthers, GUS activity was observed in tapetum cells when the modified promoter was fused to the gus gene. This promoter construct was subsequently used to drive an antisense chs gene in transgenic petunia, which led to the inhibition of pigment synthesis in anthers of five of 35 transformants. Transgenic plants with white anthers were male sterile due to an arrest in male gametophyte development. This finding indicated that flavonoids play an essential role in male gametophyte development.

Acyltransferases↗

Accumulation of deleterious mutations: additional Drosophila melanogaster estimates and a simulation of the effects of selection.

We report an assay of egg-to-adult viability in full-sibling mutation accumulation (MA) lines derived from a completely homozygous population of Drosophila melanogaster and maintained for 210 generations. A simultaneous evaluation was also made of a large population derived from the same origin and maintained as a control for the same period. We also present computer simulations to explore the possible decline in viability of the control population due to mutation accumulation and the possible effect of selection within and between MA lines. For this purpose, we used two mutational models independent from the data analyzed and based on radically different assumptions. The first model implies a large number of mutations of small effect, whereas the second implies a much smaller number of mutations with much larger effects. The observed rate of decline in mean viability was very small but significant (0.077%). The rate of increase in among line variance (0.189 x 10(-3)) was similar to those obtained previously in the same lines. The simulation results indicated that a model of many mutations of small effect is incompatible with the evolution of the mean viability of the control and MA lines over generations, the distribution of line means after 210 generations of mutation accumulation, and the pattern of line extinction over generations. Basically, this model predicted a large drop in viability, both in the control and particularly the MA lines, that is not observed empirically. It also predicted a rate of line extinction too low in the early generations and too high in the later ones. In contrast, the model based on few mutations of large effect was generally consistent with all the observations.

Animals↗

Toward a realistic model of mutations affecting fitness.

Analysis of a recent mutation accumulation (MA) experiment has led to the suggestion that as many as one-half of spontaneous mutations in Arabidopsis are advantageous for fitness. We evaluate this in the light of data from other MA experiments, along with molecular evidence, that suggest the vast majority of new mutations are deleterious.

Animals↗

Interfering with nature.

Certain kinds of medical treatment are often held to be morally unacceptable because they are an 'interference with nature'. I suggest a way in which we can make sense of such ideas. We can make significant choices only against a background of conditions which we regard as 'natural', and these will typically include such facts as those of birth and death, of youth and age, and of sexual relations. I argue, however, that such ideas, though intelligible, do not establish any valid moral objection to, for instance, the use of ovarian tissue for assisted conception.

Biomedical Technology↗