A one-step gene mapping test for identifying genetic and chromosomal abnormalities in embryos may be available in the UK within a year. The technique, known as karyo-mapping, can screen for almost any inherited disease and is much faster than those currently available as it does not need prior knowledge of the specific gene mutation involved. The method was unveiled at the annual conference of the European Society for
Human Reproduction and Embryology (ESHRE), in Amsterdam, after researchers from the UK and US announced they had successfully screened cells taken from donated embryos that were known to have cystic fibrosis (CF).
Since 1989, couples who are known to be at risk of having a child with a genetic disorder have had the option of screening their embryos using a technique called pre-implantation genetic diagnosis (PGD). PGD involves identifying the exact mutation causing a particular disease in a particular family, then spending many months developing a custom test. The process costs several thousand pounds and can only pick up two per cent of known genetic disorders.
Now, for a similar price, karyomapping can identify any known genetic disorder and is faster because scientists do not need to know the exact DNA mutation they are looking for. Instead they compare the DNA of affected and unaffected family members to work out which DNA section is carried only by those affected by the condition. Embryos can then be screened for this section of DNA to find out if they have inherited the mutation. In practice this involves DNA comparisons at over 300,000 locations genome-wide, but can be achieved rapidly through current microchip technology known as
'microarrays'. Another advantage is that karyomapping can simultaneously check for abnormal numbers of any of the 23 pairs of chromosomes, which can lead to conditions such as Down syndrome or trigger miscarriages.
'The hope is that clinicians will be able to test embryos for specific genetic diseases and know that, with one test, they are transferring chromosomally normal embryos. This will be a step forward from current technology that is mostly limited to choosing one test or the other,' explained karryomapping's inventor, Professor Alan Handyside of the London Bridge Fertility Gynaecology and Genetics Centre in London.
Some have argued the new technique may add to the controversy over 'designer babies' because it widens the range of genetic characteristics for which embryos can be screened and could theoretically be used to screen for non-serious conditions, or non-medical traits such as blue eyes. Professor Handyside believes this is not an issue because the relevant regulations in the UK are very strict and would remain so. 'We're not mad Frankensteins working away in our laboratories to create designer babies. We are only allowed to look for major diseases which cause handicaps,' he retorted.
Elsewhere at ESHRE scientists announced that up to 90 per cent of IVF embryos contain chromosomal abnormalities, even those produced by young, fertile couples. The surprising finding implies that current PGD techniques do nothing to improve pregnancy and live birth rates, and can potentially lead to viable embryos being discarded. This news means that the timely announcement of the new karyomapping method will be warmly welcomed by many.
Friday, September 4, 2009
Thursday, September 3, 2009
More Ovarian Transplants
Two studies reported at the annual conference of the European Society for Human Reproduction and Embryology (ESHRE) in Amsterdam show advances in ovarian transplant techniques. The advances could make the procedure available to women seeking to avoid fertility problems as they age.
Ovarian transplants have been primarily used as a way to preserve fertility in women undergoing treatments that damage the reproductive system, such as chemotherapy. The ovaries can be removed and frozen before such treatment begins, and then re-implanted after treatment has finished. Previously, it has only been used for women with serious disease; due to the uncertainties involved. Now, advances in the technique mean transplants are more successful, and it may be possible that the procedure can become more widely available.
In the first study Dr Sherman Silber reported that freezing ovarian tissue using vitrification gave the same success rate as using fresh tissue. Freezing ovarian tissue using the vitrification method avoids ice formation, and egg viability was almost identical to that seen in fresh tissue. Dr Silber and colleagues tested the different methods in 15 women undergoing cancer treatment. He explained that 'we found that 91.9 per cent of the fresh oocytes were viable compared with 88.9 per cent of those vitrified.
However, slow freezing resulted in a 56 per cent loss of viability. Transplantation resulted in patients regaining a normal ovarian cycle in about five months, and ovarian function lasted for four years in some of the patients. There were no differences in pregnancy rates or ovulatory menstrual cycling between the fresh and frozen grafts. In the second related study, researchers in France led by Dr Pascal
Piver reported on a technique that may improve success of ovary transplant.The technique is a two-step process, where a very small section is implanted first, and the ovary implanted three days later. This encourages blood flow and hormone supply to be quickly restored to the implanted ovary. This helps the implanted ovary to become functional - something that doctors have previously struggled to do. The procedure is also less invasive than the previous one-step method. Dr Piver reported on the first success of the technique in his clinic, saying: 'On June 22, a baby girl was born to a
mother who had been menopausal for two years as a result of treatment for sickle cell anemia. After transplanting her own ovarian tissue she started ovulating in four months and became pregnant naturally six months after transplantation. Both mother and baby are doing well.'
Experts said the possibility of healthy women being offered ovary transplants may spark controversy. 'This is not an experimental procedure for cancer patients anymore', said Dr Silber, director of the St. Louis Infertility Center in Missouri, US, adding: 'The question is whether more women should be able to have this option.'
'We are in the middle of an infertility epidemic,' he told AP news. 'With these new techniques, we could dramatically expand our reproductive lifespan', he added.
Ovarian transplants have been primarily used as a way to preserve fertility in women undergoing treatments that damage the reproductive system, such as chemotherapy. The ovaries can be removed and frozen before such treatment begins, and then re-implanted after treatment has finished. Previously, it has only been used for women with serious disease; due to the uncertainties involved. Now, advances in the technique mean transplants are more successful, and it may be possible that the procedure can become more widely available.
In the first study Dr Sherman Silber reported that freezing ovarian tissue using vitrification gave the same success rate as using fresh tissue. Freezing ovarian tissue using the vitrification method avoids ice formation, and egg viability was almost identical to that seen in fresh tissue. Dr Silber and colleagues tested the different methods in 15 women undergoing cancer treatment. He explained that 'we found that 91.9 per cent of the fresh oocytes were viable compared with 88.9 per cent of those vitrified.
However, slow freezing resulted in a 56 per cent loss of viability. Transplantation resulted in patients regaining a normal ovarian cycle in about five months, and ovarian function lasted for four years in some of the patients. There were no differences in pregnancy rates or ovulatory menstrual cycling between the fresh and frozen grafts. In the second related study, researchers in France led by Dr Pascal
Piver reported on a technique that may improve success of ovary transplant.The technique is a two-step process, where a very small section is implanted first, and the ovary implanted three days later. This encourages blood flow and hormone supply to be quickly restored to the implanted ovary. This helps the implanted ovary to become functional - something that doctors have previously struggled to do. The procedure is also less invasive than the previous one-step method. Dr Piver reported on the first success of the technique in his clinic, saying: 'On June 22, a baby girl was born to a
mother who had been menopausal for two years as a result of treatment for sickle cell anemia. After transplanting her own ovarian tissue she started ovulating in four months and became pregnant naturally six months after transplantation. Both mother and baby are doing well.'
Experts said the possibility of healthy women being offered ovary transplants may spark controversy. 'This is not an experimental procedure for cancer patients anymore', said Dr Silber, director of the St. Louis Infertility Center in Missouri, US, adding: 'The question is whether more women should be able to have this option.'
'We are in the middle of an infertility epidemic,' he told AP news. 'With these new techniques, we could dramatically expand our reproductive lifespan', he added.
Wednesday, September 2, 2009
Similar Outcomes In Babies Born Following ICSI Or IVF
Analysis of the longest running ICSI programme in the United States has found reassuring evidence that babies born from frozen embryos fertilised via ICSI (intracytoplasmic sperm injection) do just as well as those born from frozen embryos fertilised via standard IVF treatment.
The researchers also compared babies born as a result of cycles in which the women had additional hormone medication with babies born as a result of unmedicated, natural cycles, and, although they found a slightly higher rate of malformations in babies born from medicated cycles, the difference was small - 2.2% versus 0.4%.
Ms Queenie Neri, a research associate at Cornell University (New York, USA) and a member of the team headed by Professor Gianpiero Palermo who pioneered ICSI in 1992, told the 25th annual meeting of the European Society of Human Reproduction and Embryology in Amsterdam that she and her colleagues had looked at all births from frozen embryos, conceived via ICSI or IVF, between 1993 and 2007.
Ms Neri identified 720 IVF and 1231 ICSI frozen embryo transfers. The survival rate of the frozen embryos was 74% after IVF and 77.2% after ICSI. The clinical pregnancy rate was 42.8% after IVF and 39.4% after ICSI. These resulted in 84.1% IVF and 89.7% ICSI deliveries. There were 27.8% multiple IVF pregnancies and 21.1% multiple ICSI pregnancies. Outcomes at the time of birth for Apgar scores, gestational ages, birth weights and congenital malformations were similar for both IVF and ICSI singleton babies.
When she grouped the babies according to whether they came from medicated or unmedicated cycles, she found that the clinical pregnancy rate was 42.1% and 39.4% respectively; delivery rates were 86.7% (with 28.7% multiple births) and 87.5% (19.2% multiple births) respectively. Gestational ages and birth weights were similar between the two groups, but the malformation rate was 2.2% from the medicated cycles and 0.4% from the natural cycles.
Ms Neri said: "Freezing embryos as part of fertility treatment has become a fundamental part of assisted reproduction technology. We found no differences in the ability of embryo generated by IVF or ICSI to implant, even after undergoing the stress of cryopreservation. We were unable to confirm a significant benefit of the unmedicated cycle on the neonatal outcome of the cryopreserved embryos; the difference in malformation rates was small.
"The original premise of the study was to identify a difference in neonatal outcome while in the presence or absence of infertility medication, with the assumption that the unmedicated cycles would generate better offspring outcomes. Interestingly, we did not see any clear difference in neonatal outcomes between the medicated and unmedicated groups. From our study, the combination of exposure to cryopreservation and medications or both did not significantly impair offspring outcome."
The malformations ranged from heart defects to defects caused by hereditary factors and sporadic genetic mutations or interactions. However, Ms Neri said: "They were within the spectrum of malformations observed in newborns in the general population."
As there was no statistical difference between the medicated and unmedicated cycles, Ms Neri said that it was not possible to say that medicated cycles were associated with higher rates of malformations, or, if they were, what mechanism might be responsible.
"Our study reported none of the specific abnormalities linked to male factor infertility, medications or other environmental triggers such as extended in vitro culture, which have been reported by other studies," she said.
"When you think about it, the reproductive medical field has created a new sub-population. These children are now reaching puberty and their fertility status still remains to be assessed. Therefore, the continuous monitoring of children generated through artificial conception is of paramount importance," she concluded.
The researchers also compared babies born as a result of cycles in which the women had additional hormone medication with babies born as a result of unmedicated, natural cycles, and, although they found a slightly higher rate of malformations in babies born from medicated cycles, the difference was small - 2.2% versus 0.4%.
Ms Queenie Neri, a research associate at Cornell University (New York, USA) and a member of the team headed by Professor Gianpiero Palermo who pioneered ICSI in 1992, told the 25th annual meeting of the European Society of Human Reproduction and Embryology in Amsterdam that she and her colleagues had looked at all births from frozen embryos, conceived via ICSI or IVF, between 1993 and 2007.
Ms Neri identified 720 IVF and 1231 ICSI frozen embryo transfers. The survival rate of the frozen embryos was 74% after IVF and 77.2% after ICSI. The clinical pregnancy rate was 42.8% after IVF and 39.4% after ICSI. These resulted in 84.1% IVF and 89.7% ICSI deliveries. There were 27.8% multiple IVF pregnancies and 21.1% multiple ICSI pregnancies. Outcomes at the time of birth for Apgar scores, gestational ages, birth weights and congenital malformations were similar for both IVF and ICSI singleton babies.
When she grouped the babies according to whether they came from medicated or unmedicated cycles, she found that the clinical pregnancy rate was 42.1% and 39.4% respectively; delivery rates were 86.7% (with 28.7% multiple births) and 87.5% (19.2% multiple births) respectively. Gestational ages and birth weights were similar between the two groups, but the malformation rate was 2.2% from the medicated cycles and 0.4% from the natural cycles.
Ms Neri said: "Freezing embryos as part of fertility treatment has become a fundamental part of assisted reproduction technology. We found no differences in the ability of embryo generated by IVF or ICSI to implant, even after undergoing the stress of cryopreservation. We were unable to confirm a significant benefit of the unmedicated cycle on the neonatal outcome of the cryopreserved embryos; the difference in malformation rates was small.
"The original premise of the study was to identify a difference in neonatal outcome while in the presence or absence of infertility medication, with the assumption that the unmedicated cycles would generate better offspring outcomes. Interestingly, we did not see any clear difference in neonatal outcomes between the medicated and unmedicated groups. From our study, the combination of exposure to cryopreservation and medications or both did not significantly impair offspring outcome."
The malformations ranged from heart defects to defects caused by hereditary factors and sporadic genetic mutations or interactions. However, Ms Neri said: "They were within the spectrum of malformations observed in newborns in the general population."
As there was no statistical difference between the medicated and unmedicated cycles, Ms Neri said that it was not possible to say that medicated cycles were associated with higher rates of malformations, or, if they were, what mechanism might be responsible.
"Our study reported none of the specific abnormalities linked to male factor infertility, medications or other environmental triggers such as extended in vitro culture, which have been reported by other studies," she said.
"When you think about it, the reproductive medical field has created a new sub-population. These children are now reaching puberty and their fertility status still remains to be assessed. Therefore, the continuous monitoring of children generated through artificial conception is of paramount importance," she concluded.
Tuesday, September 1, 2009
Accelerated fertility treatment leads to shortened time to pregnancy and cost savings
A major new trial recently published in the journal Fertility and Sterility shows that for couples beginning infertility treatments, an accelerated path to in-vitro fertilization (IVF) can offer a shorter time to pregnancy, cost savings of nearly $10,000, and a lowered risk of multiple births.
For the first time, these results demonstrate that the long held treatment combining fertility injections with insemination (IUI) does not have a place in infertility treatments today. This study also demonstrates that today's infertility treatments are very successful. When fertility care is covered by insurance (or alternatively when couples can afford all needed treatment), the vast majority will have a baby, and the quickest way to get pregnant is to follow this new shortened protocol.
Elizabeth Ginsburg, President of the Society for Assisted Reproductive Technology, commented, "This is a very important study that will likely influence physicians to reduce the number of stimulated inseminations for patients with unexplained infertility. Adoption of such an accelerated course of treatment could result in many patients conceiving in less time with less expense."
Known as the FASTT (fast-track and standard treatment) Trial, this study is the largest of its kind to date to measure the effectiveness of contemporary infertility treatments. Led by Richard Reindollar, M.D., Chair of the Department of Obstetrics and Gynecology at Dartmouth-Hitchcock Medical Center and Dartmouth Medical School, the study omitted the gonadotropin-stimulated artificial insemination cycle that usually precedes assisted reproductive technology, for approximately one-half of the 503 participating couples.
"One key strength of the trial was the Massachusetts Infertility Mandate, which requires insurers to cover the cost of fertility treatments," said Dr. Reindollar. "Such a large trial would not have been possible in a self-pay or partial coverage environment in which the cost of care is a much larger factor in the couple's choice of therapy."
Reindollar says another strength of the study in relation to previous efforts on the subject was a large volume of patients available at a single IVF center which allowed for standardized protocols and procedures. In addition, since the study was done in cooperation with insurance companies, there was access to detailed charge data for the patients.
For the first time, these results demonstrate that the long held treatment combining fertility injections with insemination (IUI) does not have a place in infertility treatments today. This study also demonstrates that today's infertility treatments are very successful. When fertility care is covered by insurance (or alternatively when couples can afford all needed treatment), the vast majority will have a baby, and the quickest way to get pregnant is to follow this new shortened protocol.
Elizabeth Ginsburg, President of the Society for Assisted Reproductive Technology, commented, "This is a very important study that will likely influence physicians to reduce the number of stimulated inseminations for patients with unexplained infertility. Adoption of such an accelerated course of treatment could result in many patients conceiving in less time with less expense."
Known as the FASTT (fast-track and standard treatment) Trial, this study is the largest of its kind to date to measure the effectiveness of contemporary infertility treatments. Led by Richard Reindollar, M.D., Chair of the Department of Obstetrics and Gynecology at Dartmouth-Hitchcock Medical Center and Dartmouth Medical School, the study omitted the gonadotropin-stimulated artificial insemination cycle that usually precedes assisted reproductive technology, for approximately one-half of the 503 participating couples.
"One key strength of the trial was the Massachusetts Infertility Mandate, which requires insurers to cover the cost of fertility treatments," said Dr. Reindollar. "Such a large trial would not have been possible in a self-pay or partial coverage environment in which the cost of care is a much larger factor in the couple's choice of therapy."
Reindollar says another strength of the study in relation to previous efforts on the subject was a large volume of patients available at a single IVF center which allowed for standardized protocols and procedures. In addition, since the study was done in cooperation with insurance companies, there was access to detailed charge data for the patients.
Monday, August 31, 2009
Daily Sex Increases Sperm Quality, Odds Of Pregnancy
Having sex on a daily basis improves sperm quality in men, which can enhance their chances of conceiving a child, researchers reported on Tuesday.
Dr David Greening of Sydney IVF headed the new study of 118 men to show that daily ejaculation for seven days improves their sperm quality by reducing the amount of DNA damage.
Greening presented his findings to the 25th annual meeting of the European Society of Human Reproduction and Embryology in Amsterdam.
Prior to the study, researchers had debated whether or not it was necessary for men to abstain from ejaculation for a few days before attempting to conceive with their partner.
"All that we knew was that intercourse on the day of ovulation offered the highest chance of pregnancy, but we did not know what was the best advice for the period leading up to ovulation or egg retrieval for IVF,” said Greening.
"I thought that frequent ejaculation might be a physiological mechanism to improve sperm DNA damage, while maintaining semen levels within the normal, fertile range."
Greening studied 118 men with higher than normal sperm DNA damage. Men were instructed to ejaculate each day for seven consecutive days.
Before the study began, the men’s sperm had DNA damage ranging between 15 percent and 98 percent, based on the DNA fragmentation index.
On the seventh day of the study, Greening found that 96 men, or 81 percent, had an average 12 percent decrease in their sperm DNA damage. Meanwhile, 22 men, or 19 percent, had an average increase in damage of nearly 10 percent.
"Although the mean average was 26 percent which is in the 'fair' range for sperm quality, this included 18 percent of men whose sperm DNA damage increased as well as those whose DNA damage decreased. Amongst the men whose damage decreased, their average dropped by 12 percent to just under 23 percent DFI, which puts them in the 'good' range. Also, more men moved into the 'good' range and out of the 'poor' or 'fair' range. These changes were substantial and statistically highly significant,” said Greening.
"In addition, we found that although frequent ejaculation decreased semen volume and sperm concentrations, it did not compromise sperm motility and, in fact, this rose slightly but significantly.”
"Further research is required to see whether the improvement in these men's sperm quality translates into better pregnancy rates, but other, previous studies have shown the relationship between sperm DNA damage and pregnancy rates,” Greening concluded.
"The optimal number of days of ejaculation might be more or less than seven days, but a week appears manageable and favorable.”
Dr David Greening of Sydney IVF headed the new study of 118 men to show that daily ejaculation for seven days improves their sperm quality by reducing the amount of DNA damage.
Greening presented his findings to the 25th annual meeting of the European Society of Human Reproduction and Embryology in Amsterdam.
Prior to the study, researchers had debated whether or not it was necessary for men to abstain from ejaculation for a few days before attempting to conceive with their partner.
"All that we knew was that intercourse on the day of ovulation offered the highest chance of pregnancy, but we did not know what was the best advice for the period leading up to ovulation or egg retrieval for IVF,” said Greening.
"I thought that frequent ejaculation might be a physiological mechanism to improve sperm DNA damage, while maintaining semen levels within the normal, fertile range."
Greening studied 118 men with higher than normal sperm DNA damage. Men were instructed to ejaculate each day for seven consecutive days.
Before the study began, the men’s sperm had DNA damage ranging between 15 percent and 98 percent, based on the DNA fragmentation index.
On the seventh day of the study, Greening found that 96 men, or 81 percent, had an average 12 percent decrease in their sperm DNA damage. Meanwhile, 22 men, or 19 percent, had an average increase in damage of nearly 10 percent.
"Although the mean average was 26 percent which is in the 'fair' range for sperm quality, this included 18 percent of men whose sperm DNA damage increased as well as those whose DNA damage decreased. Amongst the men whose damage decreased, their average dropped by 12 percent to just under 23 percent DFI, which puts them in the 'good' range. Also, more men moved into the 'good' range and out of the 'poor' or 'fair' range. These changes were substantial and statistically highly significant,” said Greening.
"In addition, we found that although frequent ejaculation decreased semen volume and sperm concentrations, it did not compromise sperm motility and, in fact, this rose slightly but significantly.”
"Further research is required to see whether the improvement in these men's sperm quality translates into better pregnancy rates, but other, previous studies have shown the relationship between sperm DNA damage and pregnancy rates,” Greening concluded.
"The optimal number of days of ejaculation might be more or less than seven days, but a week appears manageable and favorable.”
Sunday, August 30, 2009
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