Intracytoplasmic sperm injection (ICSI), in contrast to the conventional IVF procedures, may help attain a higher rate of normal fertilization in extremely low oocyte retrieval cycles. The results of the study have been published in the recent issue of the journal Fertility and Sterility. Yu-Che Ou from the Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital, Taiwan, and colleagues, conducted a case-control study on infertile subjects with one to three oocytes per retrieval, and were divided into two groups undergoing either ICSI or IVF treatment. During the study, the cycle cancellation, fertilization, implantation and clinical pregnancy rates per transfer were observed. The study results are shown in the Table:
Although the rates of clinical pregnancy, implantation, and live births per transfer were higher in the ICSI group, the difference was not statistically significant between the two groups. Also, the cycle cancellation and complete fertilization failure rates were found to be similar in both the groups.Earlier, Requena, et al. (Journal of Assisted Reproduction and Genetics, 2000) conducted a prospective case-control study to evaluate maturation in vitro of human oocytes (MIVHO) as an alternate to IVF treatment, in low ovarian responders. Oocyte retrieval, maturation in vitro, fertilization, and blastocyst development rates were observed in spontaneously ovulatory women at the Instituto Valenciano de Infertilidad. The study results showed that the oocyte retrieval rate was considerably higher in cases where the pickup was carried out before follicular selection. The results of MIVHO in normal responders as well as low responders with an ovarian content of early antral follicles >5, were comparable. The study results demonstrated that MIVHO in low responders with an adequate number of early antral follicles could be successful and oocyte retrieval before follicular selection would aid in attaining more oocytes.
Although low ovarian response is not well defined, usually a patient with <34 oocytes, serum peak levels of <500mg/ml after aggressive stimulation, and with a background of at least two unsuccessful attempts of ovarian stimulation, is considered to be a low responder. Low ovarian reserve could be a result of high body mass index, pelvic adhesions, prior ovarian surgery, or progressive age. As the IVF outcome is directly dependent on the number of embryos available, low embryo count could result in decreased pregnancy rates.Though ICSI is associated with damage to a low percentage of injected oocytes, this micro-assisted fertilization technique is preferable in cases of oligospermia and azoospermia. Demonstrating the better performance of ICSI compared to IVF in very low oocyte retrieval cycles, the current study suggests ICSI as a superior choice for treating this condition.
References
1. Ou YC, Lan KC, Huang FJ, Kung FT, Lan TH, Chang SY. Comparison of in vitro fertilization versus intracytoplasmic sperm injection in extremely low oocyte retrieval cycles. Fertil Steril. 2008 Dec 22. [Epub ahead of print].
2. Requena A, Neuspiller F, Cobo AC, et al. The potential use of maturation in vitro of human oocytes in low responder patients. J Assist Reprod Genet. 2000 May;17(5):239-44
Showing posts with label ICSI tales. Show all posts
Showing posts with label ICSI tales. Show all posts
Thursday, February 12, 2009
Monday, January 12, 2009
Oocyte electroactivation after ICSI
Electrical activation of oocytes after ICSI can significantly improve the fertilization rate in selected patients, according to the results of a randomized controlled study.
Specialists from the Egyptian IVF-ET Center in Cairo, Egypt, conducted the study to estimate the effect of electrical activation of oocytes in patients with previously failed or limited fertilization after ICSI, and in patients likely to have failed fertilization due to teratozoospermia.
Previous research has suggested that fertilization failure occurs in an estimated 2-3 percent of ICSI cycles and is often due to the failure of oocyte activation. Past studies have provided some evidence to suggest that electrical activation (or electroactivation) of oocytes can improve success rates.
The researchers studied the effect of electrical activation in 241 ICSI cycles involving couples with severe oligoasthenospermia or azoospermia. Poor or failed fertilization was expected in these cycles because of 100 percent abnormal sperm morphology or totally immotile sperm. In all cases the female partner was under 40 years of age and had a normal hormonal profile and no pelvic pathology.
The oocytes from each patient were randomly assigned on a one-to-one basis to either electroactivation (n = 1,640) or no electroactivation (n = 1,435). Electroactivation was performed 30 minutes after ICSI, using a double-square direct current pulse, and embryo transfer was performed with the best available embryos.
The researchers (Mansour R et al) present their findings in a new paper due to be published in the journal Fertility and Sterility. They report that:
The fertilization rate was significantly higher in the electroactivation group, compared with the control group: 68 percent versus 60 percent respectively (odds ratio 1.40; 95 percent confidence interval 1.20-1.63).
There was no significant difference between the two groups in the oocyte degeneration rate (5.9 percent in the electroactivation group and 4.9 percent in the control group).
There were a total of 112 clinical pregnancies in the study. In 15 of these, the embryos transferred were derived solely from the electroactivated group (out of a total of 34 embryo transfer procedures involving such embryos – a clinical pregnancy rate of 44 percent). In 69 of the clinical pregnancies the embryos transferred were derived solely from the control group (out of a total of 69 embryo transfer procedures involving such embryos – a clinical pregnancy rate of 48 percent). In the remaining 64, the embryos transferred were derived from both groups (out of a total of 138 embryo transfer procedures – a clinical pregnancy rate of 46.4 percent).
The miscarriage rates were: 20 percent (3 out of 15 clinical pregnancies) when the embryos transferred were derived solely from the electroactivated group, 9 per cent (3 out of 33 clinical pregnancies) when the embryos transferred were derived solely from the control group, and 9.4 percent (6 out of 64 clinical pregnancies) when the embryos transferred were derived from both groups.
Total fertilization failure did not occur in the study group, but occurred in five cycles in the control group.
Concluding, the researchers write that electroactivation of oocytes after ICSI can significantly improve the chances of fertilization, but stress: “However, more studies are needed to evaluate the clinical significance and safety of this technique.
“It is recommended in cases of previous failure of fertilization or limited fertilization, as well as in cases of severe oligoasthenospermia or azoospermia with 100 percent abnormal forms or zero motility.”
Source: Fertility and Sterility 2008;in press
Specialists from the Egyptian IVF-ET Center in Cairo, Egypt, conducted the study to estimate the effect of electrical activation of oocytes in patients with previously failed or limited fertilization after ICSI, and in patients likely to have failed fertilization due to teratozoospermia.
Previous research has suggested that fertilization failure occurs in an estimated 2-3 percent of ICSI cycles and is often due to the failure of oocyte activation. Past studies have provided some evidence to suggest that electrical activation (or electroactivation) of oocytes can improve success rates.
The researchers studied the effect of electrical activation in 241 ICSI cycles involving couples with severe oligoasthenospermia or azoospermia. Poor or failed fertilization was expected in these cycles because of 100 percent abnormal sperm morphology or totally immotile sperm. In all cases the female partner was under 40 years of age and had a normal hormonal profile and no pelvic pathology.
The oocytes from each patient were randomly assigned on a one-to-one basis to either electroactivation (n = 1,640) or no electroactivation (n = 1,435). Electroactivation was performed 30 minutes after ICSI, using a double-square direct current pulse, and embryo transfer was performed with the best available embryos.
The researchers (Mansour R et al) present their findings in a new paper due to be published in the journal Fertility and Sterility. They report that:
The fertilization rate was significantly higher in the electroactivation group, compared with the control group: 68 percent versus 60 percent respectively (odds ratio 1.40; 95 percent confidence interval 1.20-1.63).
There was no significant difference between the two groups in the oocyte degeneration rate (5.9 percent in the electroactivation group and 4.9 percent in the control group).
There were a total of 112 clinical pregnancies in the study. In 15 of these, the embryos transferred were derived solely from the electroactivated group (out of a total of 34 embryo transfer procedures involving such embryos – a clinical pregnancy rate of 44 percent). In 69 of the clinical pregnancies the embryos transferred were derived solely from the control group (out of a total of 69 embryo transfer procedures involving such embryos – a clinical pregnancy rate of 48 percent). In the remaining 64, the embryos transferred were derived from both groups (out of a total of 138 embryo transfer procedures – a clinical pregnancy rate of 46.4 percent).
The miscarriage rates were: 20 percent (3 out of 15 clinical pregnancies) when the embryos transferred were derived solely from the electroactivated group, 9 per cent (3 out of 33 clinical pregnancies) when the embryos transferred were derived solely from the control group, and 9.4 percent (6 out of 64 clinical pregnancies) when the embryos transferred were derived from both groups.
Total fertilization failure did not occur in the study group, but occurred in five cycles in the control group.
Concluding, the researchers write that electroactivation of oocytes after ICSI can significantly improve the chances of fertilization, but stress: “However, more studies are needed to evaluate the clinical significance and safety of this technique.
“It is recommended in cases of previous failure of fertilization or limited fertilization, as well as in cases of severe oligoasthenospermia or azoospermia with 100 percent abnormal forms or zero motility.”
Source: Fertility and Sterility 2008;in press
Thursday, November 6, 2008
Dad's sperm linked to IQ
The results of a relatively small study suggest that children conceived using a fertility technique called intracytoplasmic sperm injection (ICSI) may have slightly lower IQ scores than children conceived naturally or with in vitro fertilisation (IVF).
ICSI is typically used for men who have low numbers of sperm in their semen or who have poor quality sperm. However, it can also be used in cases in which the mother's eggs are difficult for the sperm to penetrate.
In a laboratory, a single sperm is isolated and then directly injected into an egg removed from the prospective mother. If fertilisation is successful, the embryo that develops a few days later is transferred into the mother and the steps are then the same as with IVF.
As reported in the journal Fertility and Sterility, Dr. Sylvia Veen and colleagues from Leiden University Medical Centre, the Netherlands, compared the IQ at age five to eight years of 83 children conceived by ICSI with that of 83 children conceived by IVF and 85 conceived naturally.
They report that the average IQ, based on the Revised Amsterdam Child Intelligence Test, was 103 in the ICSI group, 107 in the IVF group, and 110 in the naturally conceived group.
The four-point difference between ICSI children and IVF children was not considered significant from a statistical standpoint, meaning that it could have occurred by chance. However, the seven-point difference in favour of naturally conceived children versus ICSI children was statistically significant.
"The ICSI children performed worse on all subtests with differences in (average) scores ranging from 0.7 to 2.1," the investigators note.
Veen and colleagues point out that "the clinical significance of the differences in IQ between ICSI children and both IVF and natural conception controls is debatable."
"On the one hand, the (average) IQ of ICSI children was within the normal range," they explain. "On the other hand, a shift of the total ICSI population to lower IQs may result in children crossing borders at the lower edge of the normal range. Indeed, ICSI children more often scored less than 85 than natural conception children."
ICSI is typically used for men who have low numbers of sperm in their semen or who have poor quality sperm. However, it can also be used in cases in which the mother's eggs are difficult for the sperm to penetrate.
In a laboratory, a single sperm is isolated and then directly injected into an egg removed from the prospective mother. If fertilisation is successful, the embryo that develops a few days later is transferred into the mother and the steps are then the same as with IVF.
As reported in the journal Fertility and Sterility, Dr. Sylvia Veen and colleagues from Leiden University Medical Centre, the Netherlands, compared the IQ at age five to eight years of 83 children conceived by ICSI with that of 83 children conceived by IVF and 85 conceived naturally.
They report that the average IQ, based on the Revised Amsterdam Child Intelligence Test, was 103 in the ICSI group, 107 in the IVF group, and 110 in the naturally conceived group.
The four-point difference between ICSI children and IVF children was not considered significant from a statistical standpoint, meaning that it could have occurred by chance. However, the seven-point difference in favour of naturally conceived children versus ICSI children was statistically significant.
"The ICSI children performed worse on all subtests with differences in (average) scores ranging from 0.7 to 2.1," the investigators note.
Veen and colleagues point out that "the clinical significance of the differences in IQ between ICSI children and both IVF and natural conception controls is debatable."
"On the one hand, the (average) IQ of ICSI children was within the normal range," they explain. "On the other hand, a shift of the total ICSI population to lower IQs may result in children crossing borders at the lower edge of the normal range. Indeed, ICSI children more often scored less than 85 than natural conception children."
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