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ESHRE offers to help UK government decide about human cloning
Experts give practical advice in reproductive medicine f cervical trauma can be avoided during embryo transfer for in-vitro fertilisation, then pregnancy can result even after the most technically challenging procedures, reported Leif Hägglund (International Fertility Centre, Malmö, Sweden) and coworkers at the annual meeting of the European Society of Human Reproduction and Embryology (ESHRE; Tours, France; June 27–30). There have been few attempts to identify which aspects of transcervical embryo transfer are related to outcome, said Hägglund, adding that the results of their prospective study had encouraged his team to develop “better fingers” to avoid cervical trauma. Hägglund and colleagues developed a two-variable scoring system for embryo transfer. The presence of
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blood on the catheter or its outer sheath after transfer was taken as an indicator of the degree of cervical or endometrial trauma (no blood; blood in or on the outer sheath; blood in or on the catheter). The degree of technical difficulty was scored from no difficulty to major problems requiring a change of catheter. Between January, 1995, and December, 1998, 1651 embryo transfers were done after in-vitro fertilisation or intracytoplasmic sperm injection treatments, resulting in 577 pregnancies. Fewer pregnancies resulted from transfers where blood was in or on the catheter sheath than when there was no blood (clinical pregnancies/embryo transfers 54/192 [28%] vs 518/1410 [37%]; p<0·05). Even fewer pregnancies occurred where there had
ESHRE offers to help UK government decide about human cloning On June 28, ESHRE said that it will be offering UK ministers its services for a new advisory group which is to assess the potential benefits of the use of human cloning techniques for therapeutic purposes. The UK government announced the new expert group on June 24 in its response to last year’s joint report on cloning by the Human Fertilisation and Embryology Authority and the Human Genetics Advisory Commission. In its statement, the government reaffirmed its policy that “human cloning is ethically unacceptable”. In addition, it stated that more evidence of benefit was needed before research could be allowed into therapeutic cloning techniques that might provide tissue for transplantation and ways to prevent mitochondrial diseases. Lynn Fraser, new chair of ESHRE, noted that ESHRE had agreed to a voluntary moratorium on human cloning for reproduction, but said that “if we are to be able to develop potential new treatments for serious human diseases . . . research on cloned human cells is essential”. Jane Bradbury
been blood in or on the catheter (5/49 [10%]; p<0·01). By contrast, there were no significant differences when transfers were grouped by technical difficulty of procedure. 328 (38%) pregnancies resulted from 861 transfers that presented no difficulty; 10 (23%) pregnancies resulted from 44 highly problematic transfers. The researchers found that their results were unaffected by the woman’s age, the number of eggs collected, or the embryo quality. The clinical nature of Hägglund’s work—representing, as one speaker put it “the forgotten face of IVF”—contrasted with the many presentations at ESHRE based on smallsample laboratory work. Indeed, in bemoaning the poor representation of randomised trials and the small sample sizes in reproductive medicine studies, Richard Lilford (NHS Executive, Birmingham, UK) made a plea for ESHRE to develop a system of pre-trial registration to avoid publication bias. His plea was endorsed by Johannes Evers (Academisch Ziekenhuis, Maastricht, Netherlands), who said that an ongoing follow-up of trials presented at ESHRE conferences from 1992 to 1997 indicated a link between drugindustry sponsorship and non-publication of negative or equivocal data. Sarah Ramsay
Ukrainian thyroid-cancer rates greatly increased since Chernobyl hyroid cancers have increased tenfold among Ukrainian children since the 1986 Chernobyl nuclear power station disaster. And most of the malignancies are unusually aggressive and rapidly metastasise to nearby lymph nodes, reports a new epidemiological study (Cancer 1999; 86: 148–55). Researchers at the Ukraine Academy of Medical Sciences in Kiev found that the number of paediatric thyroid carcinomas had increased from 12 per year before the accident to 73 per year in 1997. In the immediate Chernobyl area, the incidence of thyroid cancer has now reached 1 in 3700 of the population, more than 500-fold higher than the pre-disaster
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THE LANCET • Vol 354 • July 3, 1999
rate. Even higher rates have been recorded in nearby Belarus, which received more iodine-131 fallout than Ukraine. Children who were younger than 4years old or were in utero at the time of the accident are at the highest risk, accounting for 42% of the cases. “Children constitute the most vulnerable group of exposed individuals because their thyroid sensitivity to radiation is high, and there is a longer life span to manifest its effects”, says Virginia LiVolsi (University of Pennsylvania Medical Center, Philadelphia, PA, USA), a co-author on the study. Children who developed thyroid cancer probably ingested 131I mainly
from cow’s milk, says John Harrison, head of WHO’s collaborating centre on radiation. Iodine deficiency among the local population and their reliance on subsistence farming also contributed to the increased cancer rates, he says, and “the disaster was made worse by the absence of contingency plans to substitute contaminated food with safe food from elsewhere and inadequate stocks of stable iodine for prophylaxis”. Most of the children with thyroid cancer have had a thyroidectomy. More than 60% of them needed lymph-node dissection to remove metastases—a much higher rate than is usual in paediatric thyroid carcinomas. The survival rate is very high, but patients will need thyroxine for the rest of their lives, a long-term and expensive health problem for the region. Peter Mitchell
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blood on the catheter or its outer sheath after transfer was taken as an indicator of the degree of cervical or endometrial trauma (no blood; blood in or on the outer sheath; blood in or on the catheter). The degree of technical difficulty was scored from no difficulty to major problems requiring a change of catheter. Between January, 1995, and December, 1998, 1651 embryo transfers were done after in-vitro fertilisation or intracytoplasmic sperm injection treatments, resulting in 577 pregnancies. Fewer pregnancies resulted from transfers where blood was in or on the catheter sheath than when there was no blood (clinical pregnancies/embryo transfers 54/192 [28%] vs 518/1410 [37%]; p<0·05). Even fewer pregnancies occurred where there had
ESHRE offers to help UK government decide about human cloning On June 28, ESHRE said that it will be offering UK ministers its services for a new advisory group which is to assess the potential benefits of the use of human cloning techniques for therapeutic purposes. The UK government announced the new expert group on June 24 in its response to last year’s joint report on cloning by the Human Fertilisation and Embryology Authority and the Human Genetics Advisory Commission. In its statement, the government reaffirmed its policy that “human cloning is ethically unacceptable”. In addition, it stated that more evidence of benefit was needed before research could be allowed into therapeutic cloning techniques that might provide tissue for transplantation and ways to prevent mitochondrial diseases. Lynn Fraser, new chair of ESHRE, noted that ESHRE had agreed to a voluntary moratorium on human cloning for reproduction, but said that “if we are to be able to develop potential new treatments for serious human diseases . . . research on cloned human cells is essential”. Jane Bradbury
been blood in or on the catheter (5/49 [10%]; p<0·01). By contrast, there were no significant differences when transfers were grouped by technical difficulty of procedure. 328 (38%) pregnancies resulted from 861 transfers that presented no difficulty; 10 (23%) pregnancies resulted from 44 highly problematic transfers. The researchers found that their results were unaffected by the woman’s age, the number of eggs collected, or the embryo quality. The clinical nature of Hägglund’s work—representing, as one speaker put it “the forgotten face of IVF”—contrasted with the many presentations at ESHRE based on smallsample laboratory work. Indeed, in bemoaning the poor representation of randomised trials and the small sample sizes in reproductive medicine studies, Richard Lilford (NHS Executive, Birmingham, UK) made a plea for ESHRE to develop a system of pre-trial registration to avoid publication bias. His plea was endorsed by Johannes Evers (Academisch Ziekenhuis, Maastricht, Netherlands), who said that an ongoing follow-up of trials presented at ESHRE conferences from 1992 to 1997 indicated a link between drugindustry sponsorship and non-publication of negative or equivocal data. Sarah Ramsay
Ukrainian thyroid-cancer rates greatly increased since Chernobyl hyroid cancers have increased tenfold among Ukrainian children since the 1986 Chernobyl nuclear power station disaster. And most of the malignancies are unusually aggressive and rapidly metastasise to nearby lymph nodes, reports a new epidemiological study (Cancer 1999; 86: 148–55). Researchers at the Ukraine Academy of Medical Sciences in Kiev found that the number of paediatric thyroid carcinomas had increased from 12 per year before the accident to 73 per year in 1997. In the immediate Chernobyl area, the incidence of thyroid cancer has now reached 1 in 3700 of the population, more than 500-fold higher than the pre-disaster
T
THE LANCET • Vol 354 • July 3, 1999
rate. Even higher rates have been recorded in nearby Belarus, which received more iodine-131 fallout than Ukraine. Children who were younger than 4years old or were in utero at the time of the accident are at the highest risk, accounting for 42% of the cases. “Children constitute the most vulnerable group of exposed individuals because their thyroid sensitivity to radiation is high, and there is a longer life span to manifest its effects”, says Virginia LiVolsi (University of Pennsylvania Medical Center, Philadelphia, PA, USA), a co-author on the study. Children who developed thyroid cancer probably ingested 131I mainly
from cow’s milk, says John Harrison, head of WHO’s collaborating centre on radiation. Iodine deficiency among the local population and their reliance on subsistence farming also contributed to the increased cancer rates, he says, and “the disaster was made worse by the absence of contingency plans to substitute contaminated food with safe food from elsewhere and inadequate stocks of stable iodine for prophylaxis”. Most of the children with thyroid cancer have had a thyroidectomy. More than 60% of them needed lymph-node dissection to remove metastases—a much higher rate than is usual in paediatric thyroid carcinomas. The survival rate is very high, but patients will need thyroxine for the rest of their lives, a long-term and expensive health problem for the region. Peter Mitchell
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