Women donate eggs for two reasons. Firstly for other women to conceive and, secondly, for research. Both are dogged by controversy on medical, societal and financial grounds. The US and the UK are currently trying to create guidelines and legislation that will allow workers in assisted reproduction and laboratory research to operate without fear of prosecution.
Infertile women undergoing IVF are usually given some form of gonadotropin-releasing hormone to stimulate multiple oocyte production. This hyperstimulation and harvesting results in more oocytes than can be used in fertilisation and embryo transfer in any given cycle, so there are spare oocytes for later use by the woman, or for donation.
Whether the stimulation should be with GnRH agonists or antagonists is one debate and another is whether one or two embryos should be transferred. What is not in question is that the demand for oocytes far exceeds supply. Women below the age of 35 years have significantly higher IVF success rates than older women, precisely the group who are now more often seeking reproductive assistance. The result is that the donation or sale of oocytes has become a big issue.
Clearly the unauthorised harvesting of oocytes is illegal as an Israeli doctor has found to his cost (BMJ 2007;334:557), but what about consented donations to infertile women? The free donation of “extra ova” from women to their infertile fellow patients seems straight-forward enough, but already the problem of incentives has arisen. In private clinics, can these spare oocytes be bought or can the woman be given a discount for her treatment if she donates? This discount for donation occurs in the UK where 75% of all IVF procedures are funded by the patients themselves despite decrees that all infertile couples are entitled to four IVF cycles within the NHS (Ledger Lancet 2007;369:717-8). Moving further along the continuum, is it acceptable for a woman who has no fertility problems to supply oocytes for payment? In the US it is, where thousands of babies are born annually from oocytes acquired from women who receive an average of $5 000 per harvest (Spar NEJM 2007;356:1289-91).
The UK has the Human Fertilisation and Embryology Authority which is the regulator of IVF treatment. It has now ruled that altruistic oocyte donation, in conjunction with fertility treatment or not, is acceptable. The report by Mayor (BMJ 2007;334:445) made no mention of discounts for donations in the private sector - also known as “egg sharing” - so compensation for co-operation remains a grey area. Other places such as Singapore, Israel and South Korea allow donations but without payment or personal benefit.
The role of oocytes in research is more complex, despite the fact they may not be bought for study purposes. Research falls into two categories - infertility or stem cell research. The former is not as contentious, despite using human reproductive material, but the latter is highly controversial using somatic-cell nuclear transfer (SCNT) to create lines of stem cells from which the US administration has withheld federal funding. The arguments go that without payment women will not donate oocytes for research but, attracted by pay, women could be tempted to “sell their eggs” in a competitive market to their own potential detriment.
17 May, 2007
15 May, 2007
OCs and ovarian cancer
Oral contraceptives (OCs) are known to decrease a woman's risk of developing epithelial ovarian cancer. However, the dose of estrogens and progestins in OCs have come down in recent years so it is unclear if the protection previously offered still holds.
Lurie et al (Obstets Gynecol 2007;109:597-607) conducted a case-controlled study on over 700 women with epithelial ovarian cancer that took into account the woman's OC history and matched them with controls who may or may not have used OCs. Their results were conclusive. OCs were effective in decreasing the risk of cancer and the lowest formulations offered the strongest protection. The authors postulate that the antiovulatory mechanisms of OCs are the key factor in reducing malignancy rates and that women taking the lower dose pills are more likely to be compliant compared to high-dose users.
Consistency of use, rather than the hormonal dose probably explains the effect and a reduction in ovarian cancers may well continue due to OC use.
Lurie et al (Obstets Gynecol 2007;109:597-607) conducted a case-controlled study on over 700 women with epithelial ovarian cancer that took into account the woman's OC history and matched them with controls who may or may not have used OCs. Their results were conclusive. OCs were effective in decreasing the risk of cancer and the lowest formulations offered the strongest protection. The authors postulate that the antiovulatory mechanisms of OCs are the key factor in reducing malignancy rates and that women taking the lower dose pills are more likely to be compliant compared to high-dose users.
Consistency of use, rather than the hormonal dose probably explains the effect and a reduction in ovarian cancers may well continue due to OC use.
07 May, 2007
Contralateral breast cancer
Some women diagnosed with early breast cancer in one breast are later found to have cancer in the other breast. Even careful clinical examination and mammography can fail to identify early lesions, so the question arises as to whether more extensive investigations - such as magnetic resonance imaging (MRI) - should not be carried out routinely at the time of the initial diagnosis.
Lehman et al (NEJM 2007;356:1295-303) report on nearly 1 000 women across the US who had early cancer in one breast with negative mammography and clinical examination in the other who then had MRI of the “cancer-free” breast. Within one year of the initial diagnosis they found 3% of the women had or developed cancer in the contralateral breast.
The sensitivity and specificity were not as high as ideally required in a screening test but, with a negative predictive value of 99%, women may well find it acceptable. The cancers found in the contralateral breast were all early and had not spread so MRI evaluation should be considered if malignancy is found in one breast, even if routine investigations are apparently negative.
Lehman et al (NEJM 2007;356:1295-303) report on nearly 1 000 women across the US who had early cancer in one breast with negative mammography and clinical examination in the other who then had MRI of the “cancer-free” breast. Within one year of the initial diagnosis they found 3% of the women had or developed cancer in the contralateral breast.
The sensitivity and specificity were not as high as ideally required in a screening test but, with a negative predictive value of 99%, women may well find it acceptable. The cancers found in the contralateral breast were all early and had not spread so MRI evaluation should be considered if malignancy is found in one breast, even if routine investigations are apparently negative.
06 May, 2007
Exercise after breast cancer
There is evidence that regular exercise is associated with a decreased risk of breast cancer. What is less clear is whether supervised exercise for women recovering from early breast cancer treatment is beneficial. A controlled trial from Scotland now answers some quality-of-life questions.
Mutrie et al (BMJ 2007;334:517-20) followed 100 women allocated to group exercise and 100 controls for three months after their initial treatment and found the exercise group derived functional and psychological benefit, which was immediate and sustained at six months.
It is suggested that the diagnosis of cancer affords a “teachable moment” when people are receptive to changes in lifestyle behaviours and the rigorous research indicates recovery from breast cancer therapy can be enhanced by seizing that moment.
Mutrie et al (BMJ 2007;334:517-20) followed 100 women allocated to group exercise and 100 controls for three months after their initial treatment and found the exercise group derived functional and psychological benefit, which was immediate and sustained at six months.
It is suggested that the diagnosis of cancer affords a “teachable moment” when people are receptive to changes in lifestyle behaviours and the rigorous research indicates recovery from breast cancer therapy can be enhanced by seizing that moment.
03 May, 2007
Women's diets
Obesity is at an all-time high. Humans throughout the world are consuming more calories than they expend, and BMIs continue to rise. Medically this is not good news as there are virtually no benefits from being overweight - and considerable risks.
Obesity is linked to risks of cardiovascular disease, metabolic disorders, cancer incidence, increased mortality and, in women, reproductive dysfunction. Science has produced evidence of the risks and no-one in the developed world can claim ignorance of the dangers of obesity.
Socially, some developing cultures perceive obesity as a marker of success or status but the ample figure is not admired or respected in Western culture. Over the last half century, affluence seems to have changed our views and being overweight has become a feature of society. Whether it has become socially acceptable or not is a sociological question, but medically it simply increases the burden of disease.
The aesthetics are in the eye of the beholder.
Premenopausal women are traditionally figure-conscious, and diets feature in conversations, magazines and respected medical journals. Arguments about diets will continue as “easier” ways to lose weight are touted by the popular press. But is there science to back one diet against another?
Gardner et al from California (JAMA 2007;297:969-77) explored the relative merits of diets that varied in their carbohydrate components. They diligently followed four groups of women in their forties over one year who were randomly allocated to the following diets - Atkins (very low carbo), Zone (low carbo), LEARN (moderate carbo) and Ornish (very high carbo). They looked at metabolic effects and gave the women every incentive - including a modest financial stipend - to stick to their regimens.
The Atkins diet gave the best results biochemically and cardiovascularly and in terms of sustained weight loss compared to the three others which were equally inferior. However, the overall results were only modest, with the Atkins diet women losing about 4.5kg and the others about 2kg over the year.
Since their mean weight at the start was 85kg, the reward for these women's efforts was small and the drop-out rates not insignificant. Obesity is a problem of lifestyle and the individual effects are there for everyone to ponder. Medicine can highlight what each person can eat for optimal health and emphasise through large studies how our society is slumping into soft-option acceptance of unhealthy food consumption.
Obesity is linked to risks of cardiovascular disease, metabolic disorders, cancer incidence, increased mortality and, in women, reproductive dysfunction. Science has produced evidence of the risks and no-one in the developed world can claim ignorance of the dangers of obesity.
Socially, some developing cultures perceive obesity as a marker of success or status but the ample figure is not admired or respected in Western culture. Over the last half century, affluence seems to have changed our views and being overweight has become a feature of society. Whether it has become socially acceptable or not is a sociological question, but medically it simply increases the burden of disease.
The aesthetics are in the eye of the beholder.
Premenopausal women are traditionally figure-conscious, and diets feature in conversations, magazines and respected medical journals. Arguments about diets will continue as “easier” ways to lose weight are touted by the popular press. But is there science to back one diet against another?
Gardner et al from California (JAMA 2007;297:969-77) explored the relative merits of diets that varied in their carbohydrate components. They diligently followed four groups of women in their forties over one year who were randomly allocated to the following diets - Atkins (very low carbo), Zone (low carbo), LEARN (moderate carbo) and Ornish (very high carbo). They looked at metabolic effects and gave the women every incentive - including a modest financial stipend - to stick to their regimens.
The Atkins diet gave the best results biochemically and cardiovascularly and in terms of sustained weight loss compared to the three others which were equally inferior. However, the overall results were only modest, with the Atkins diet women losing about 4.5kg and the others about 2kg over the year.
Since their mean weight at the start was 85kg, the reward for these women's efforts was small and the drop-out rates not insignificant. Obesity is a problem of lifestyle and the individual effects are there for everyone to ponder. Medicine can highlight what each person can eat for optimal health and emphasise through large studies how our society is slumping into soft-option acceptance of unhealthy food consumption.
April JASS
Colleague,
Life-style continues to be a theme that the journals publish for women's health.
There are healthy, weight-reducing diets and exercise on the one hand, and the disadvantages of obesity on the other. Scientific evidence backs sensible eating and physical activity.
These are refreshing data because one might have anticipated research in the 21st century to be moving towards molecular and genetic studies. The fact that epidemiology which describes the maintenance of health is reported, allows us to advise patients about what they can do to help themselves to better health.
The issue of supplementation to prevent congenital abnormalities seems a “no brainer” but most European countries have yet to implement the practice. Is it democracy gone mad that makes them kowtow to mavericks and often whacky science that opposes such enhancement to prevent neural tube and facial cleft defects?
Evidence-based medicine has resulted in major changes in obstetric management yet it seems politicians are reluctant to heed its logic. It should be a cause that O&G societies in each country should be lobbying for - as well as fluoride addition to drinking water.
Life-style continues to be a theme that the journals publish for women's health.
There are healthy, weight-reducing diets and exercise on the one hand, and the disadvantages of obesity on the other. Scientific evidence backs sensible eating and physical activity.
These are refreshing data because one might have anticipated research in the 21st century to be moving towards molecular and genetic studies. The fact that epidemiology which describes the maintenance of health is reported, allows us to advise patients about what they can do to help themselves to better health.
The issue of supplementation to prevent congenital abnormalities seems a “no brainer” but most European countries have yet to implement the practice. Is it democracy gone mad that makes them kowtow to mavericks and often whacky science that opposes such enhancement to prevent neural tube and facial cleft defects?
Evidence-based medicine has resulted in major changes in obstetric management yet it seems politicians are reluctant to heed its logic. It should be a cause that O&G societies in each country should be lobbying for - as well as fluoride addition to drinking water.
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