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1.
精子形态变化对体外受精率的影响 总被引:5,自引:0,他引:5
目的:通过对ICSI和IVF受精率的统计,比较精子形态中的精子正常形态率、头部畸形率、畸形精子指数(TZI)和精子畸形指数(SDI)对受精结果的影响。方法:用Krger's严格标准法分别计算每组样本的精子正常形态率、头部畸形率、TZI和SDI值,与受精率进行比较。结果:①IVF组和ICSI组的受精率,与精子正常形态率、头部畸形率、TZI、SDI均无相关性。②IVF组和ICSI组中SDI>1.6和SDI<1.6的受精率、优质胚胎率和临床妊娠率差异均无统计学意义(P>0.05)。③IVF组和ICSI组中精子正常形态率≤15%与精子正常形态率>15%的二组间受精率、优质胚胎率和临床妊娠率的差异均无统计学意义(P>0.05)。结论:精子形态在体外受精时对受精率无影响,不能用精子形态来直接评价体外受精的结果。 相似文献
2.
Vernaeve V Bonduelle M Tournaye H Camus M Van Steirteghem A Devroey P 《Human reproduction (Oxford, England)》2003,18(10):2093-2097
BACKGROUND: Registries on outcome of ICSI pregnancies obtained with testicular sperm do not differentiate between obstructive (OA) and non-obstructive azoospermia (NOA). We evaluated the pregnancy outcome and neonatal data on children born after ICSI using testicular sperm of men with histologically proven OA or NOA. METHODS: Pregnancies obtained after ICSI using testicular sperm of men with defined NOA (n = 70) were compared with those of men with OA (n = 204). RESULTS: Multiple birth rates in NOA and OA couples, respectively, were 21 versus 27% (P = NS), overall preterm delivery rates were 38 versus 26% (NS), and prematurity rates were 24 versus 13% for singletons (NS) and 86 versus 54% for twins (relative risk 1.59, 95% confidence interval 1.04-2.42). Median gestational age for singletons was 38.3 versus 39.3 weeks, respectively (P < 0.05). The low birth weight rates were 34 versus 31%, respectively (NS). The early perinatal mortality rate was 66 versus 15 per 1000 births, respectively, (NS). Major congenital malformations were observed in 4 versus 3%, respectively, of the live born babies (NS). Prenatal karyotypes showed 7% de-novo abnormalities in the NOA group versus 1% in the OA group (NS). CONCLUSIONS: Our data do not show differences between NOA and OA pregnancies except for a strong tendency towards a lower gestational age in singletons and a higher percentage of premature twins in the NOA group. Although our data are based on a limited sample, the differences observed call for further analysis. Given the low pregnancy rates after ICSI with NOA, a multicentre study, differentiating NOA and OA patients, would be recommended. 相似文献
3.
Rescue ICSI of oocytes that failed to extrude the second polar body 6 h post-insemination in conventional IVF 总被引:19,自引:0,他引:19
BACKGROUND: Attempts to 'rescue' by ICSI oocytes that remained unfertilized 24 h after conventional IVF have generally resulted in poor outcomes. The aim of the present study was to compare the outcome of rescue ICSI performed on one group of patients 6 h after initial insemination with those of another group where rescue ICSI was performed 22 h after initial insemination. METHODS: Twenty-five patient IVF cycles provided the oocytes for rescue ICSI 6 h after initial insemination, and 20 cycles provided the oocytes for rescue ICSI 22 h after initial insemination in this retrospective study. Fertilization and cleavage rates, embryo quality, implantation, and pregnancy rates after rescue ICSI were the main outcome measures. RESULTS: A fertilization rate of 70.3% was achieved with 6 h rescue ICSI compared with 48.5% with 22 h rescue ICSI (P < 0.0001). From 6 h rescue ICSI, 12 clinical pregnancies (48.0%) resulted in three sets of twins, eight singletons and one abortion. From 22 h rescue ICSI there was one (5.0%) singleton pregnancy and delivery of a healthy baby. Likewise, the implantation rate was 20.2% from 6 h rescue ICSI compared with 1.72% from 22 h rescue ICSI (P < 0.02). CONCLUSIONS: Rescue ICSI after 6 h post-insemination (46 h post-HCG) gave better fertilization, pregnancy and implantation rates compared with rescue ICSI after 22 h when oocytes have become aged. 相似文献
4.
Sperm pathology is presented as the discipline of characterizing structural and functional deficiencies in abnormal spermatozoa. This concept complements that of sperm morphology mainly concerned with the appearance of spermatozoa. These two notions collaborate in providing correlations of prognostic value with sperm fertilizing capacity, explaining the mechanisms of sperm inefficiency, suggesting strategies to improve fertilization and opening a door to molecular genetic studies. Phenotypes of genetic origin involving sperm heads, flagella and the neck region are presented describing their clinical manifestations, sperm structure, cytochemistry and genetic background. When available, animal models are used to highlight possible genetic mechanisms. Sperm pathologies secondary to andrological conditions or environmental factors are described, stressing the non-specific nature of the sperm response to noxious agents. The available literature on the prognostic value of sperm pathologies in ICSI is also reviewed. Flagellar anomalies bear a good prognosis, but those affecting the acrosome, sperm chromatin and the neck region entail an increasing chance of failure, which highlights the differential roles played by specific sperm components in fertilization, implantation and early embryonic development. A final discussion is devoted to genetic counselling and the risks involved in using immotile or abnormal spermatozoa in assisted reproduction. 相似文献
5.
The effects of meiosis activating sterol on in-vitro maturation and fertilization of human oocytes from stimulated and unstimulated ovaries 总被引:3,自引:0,他引:3
Cavilla JL Kennedy CR Baltsen M Klentzeris LD Byskov AG Hartshorne GM 《Human reproduction (Oxford, England)》2001,16(3):547-555
The object of this study was to assess functional maturation in vitro by obtaining data on the fertilization and embryonic competence of human oocytes with or without exposure to meiosis activating sterol (MAS) during maturation in vitro. Immature oocytes were either collected from unstimulated patients with polycystic ovaries (PCO) during gynaecological surgery, or were donated by patients undergoing a cycle of intracytoplasmic sperm injection (ICSI) treatment including ovarian stimulation with gonadotrophins. PCO oocytes had variable cumulus cover, which was retained during culture while those from ICSI patients were cultured without cumulus. The study included 119 oocytes from PCO patients and 72 from ICSI patients. The oocytes were allowed to mature in vitro for up to 46 h in the presence or absence of MAS. Mature oocytes were inseminated by ICSI with fertile donor spermatozoa and embryo development was monitored in vitro. MAS (30 microg/ml) significantly increased the survival of oocytes from PCO patients (P < 0.01) but did not significantly affect the proportion completing maturation in vitro. For the ICSI patients, >90% of oocytes survived in all culture groups, regardless of MAS addition, however MAS (10 or 30 microg/ml) significantly increased the proportion of oocytes maturing in vitro (P < 0.05). The apparent tendency towards improved subsequent development in vitro will require larger numbers of oocytes for evaluation. Oocytes from ICSI patients matured more rapidly in vitro than those from PCO patients. Our results show positive effects of MAS on human oocytes, confirming previous data in mice. This work may have implications for the future clinical application of IVM. 相似文献
6.
Increased incidence of numerical chromosome abnormalities in spermatozoa injected into human oocytes by ICSI 总被引:6,自引:0,他引:6
The potential risk of transmitting chromosomally abnormal spermatozoa from infertile males into oocytes through intracytoplasmic sperm injection (ICSI) has prompted us to investigate the male pronuclei of tripronuclear zygotes (3PN) obtained after ICSI. To specify the type of anomalies, we used triple colour fluorescent in-situ hybridization (FISH) with three specific probes for chromosomes X, Y and 18. From a total of 163 paternal complements of ICSI-3PN zygotes, 90 (55.2%) had Y-chromosome signals. Eighty-three of these were normal, four had the disomy XY and three were diploid. In the remaining 73 ICSI-3PN zygotes without Y-chromosome signals, the origin of paternal pronuclei was extrapolated through chromosome constitution of the first polar body. Five anomalies were found in this group of zygotes, giving a total rate of numerical chromosome aberrations for fertilizing spermatozoa of 7.4%. In contrast to ICSI, only two disomies (1.5%) were found in the control group of IVF-3PN zygotes. Compared with the incidence of chromosome anomalies between paternal-derived pronuclei of ICSI- and IVF-3PN zygotes, the difference was statistically significant (P < 0.025). This study provides the first direct evidence of a higher incidence of numerical chromosome anomalies in sperm-fertilized human oocytes after ICSI. 相似文献
7.
Tucker M.J.; Morton P.C.; Wright G.; Ingargiola P.E.; Sweitzer C.L.; Elsner C.W.; Mitchell-Leef D.E.; Massey J.B. 《Human reproduction (Oxford, England)》1996,11(11):2434-2437
In two separate prospectively randomized trials, intracytoplasmicsperm injection (ICSI) cycles were studied in a controlled mannerto monitor the effects of either bovine oviductal epithelialcell co-culture (n = 119) or assisted hatching by zona drilling(n = 100). In the first study, immediately following ICSI, alleggs were placed directly either onto partial monolayers ofbovine oviductal cells or into regular culture medium. Althoughthe embryo developmental rate was apparently compromised inpart by the presence of the co-culture cells, ultimately therewere no significant differences in either the viable pregnancyrate (31.6% co-culture versus 29.0% control) or the embryonicimplantation rate (11.4% co-culture versus 13.6% control). Assistedhatching also had no significant impact on ICSI cycle outcomein terms of either the viable pregnancy rate (30.0% assistedhatching versus 32.0% control) or the embryonic implantationrate (8.5% assisted hatching versus 13.5% control). However,in female patients aged 235 years, assisted hatching appearedto convey a marginally significant benefit in terms of boththe viable pregnancy rate (35.5% assisted hatching versus 11.1%control) and the embryonic implantation rate (103% assistedhatching versus 3.1 % control). It seems that the overall improvementof ICSI cycle outcome cannot be achieved by the general applicationof either co-culture or assisted hatching. Nevertheless, itis possible that there remain specific patient groups that mightbenefit from selected use of either of these modalities. 相似文献
8.
Morel F Gallon F Amice V Le Bris MJ Le Martelot MT Roche S Valéri A Derrien V Herry A Amice J De Braekeleer M 《Human reproduction (Oxford, England)》2002,17(10):2552-2555
BACKGROUND: Several studies have shown an increased frequency of constitutional chromosome aberrations in male and female partners of couples examined prior to ICSI. We conducted a cohort study to determine whether there was an increase in numerical sex chromosome mosaicism among couples undergoing ICSI compared with fertile couples. METHODS: Cytogenetic investigations were performed in 228 females and 208 males seen for ICSI between January 1997 and March 2001. They were matched to control females and males. RESULTS: Sex chromosome loss or gain was observed in at least one cell from 24.1% of ICSI women in comparison with 22% of controls (not significant). A significant difference between these two groups was found when X chromosome loss in at least two cells was considered, 9.6% for ICSI females versus 4.8% for controls (P = 0.01). No significant difference was observed between male groups concerning loss or gain of the X or Y chromosome. CONCLUSION: Our results support previously published studies indicating that the loss of an X chromosome in a single cell in females undergoing ICSI is probably an artefact. However, they suggest that a woman could have true sex chromosome mosaicism when two 45,X0 cells are found. 相似文献
9.
de Oliveira NM Vaca Sánchez R Rodriguez Fiesta S Lopez Salgado T Rodríguez R Bethencourt JC Blanes Zamora R 《Human reproduction (Oxford, England)》2004,19(2):262-265
BACKGROUND: There are few reports of pregnancy using immotile sperm, and none using a purely mechanical assessment of viability. METHODS: In this pilot study, we retrospectively analysed 66 cycles in 61 patients with determinant male factor, recording rates of fertilization, implantation, normal pregnancy and take-home babies achieved with ICSI. Sperm selection was based on morphologically normal appearance under the inverted microscope. Viability of immotile spermatozoa was assessed by the mechanical touch technique to observe tail flexibility and tail shape recovery. RESULTS: Of 17 ICSI cycles using frozen-thawed testicular sperm, six microinjected with immotile and 11 with motile sperm, we achieved fertilization rates of 65.7 and 74.3%, respectively, and five pregnancies (two and three, respectively). Of 49 ICSI cycles using fresh testicular sperm, 10 microinjected with immotile and 39 with motile sperm, we achieved fertilization rates of 73.4 and 64.4%, respectively, and 12 pregnancies (three and nine, respectively). CONCLUSIONS: Immotile (fresh and frozen-thawed) testicular sperm of normal morphological appearance can be used to achieve clinical pregnancy with ICSI. Our results strongly suggest that immotile sperm viability can be assessed by the mechanical touch technique. 相似文献
10.
Yanagida K Katayose H Hirata S Yazawa H Hayashi S Sato A 《Human reproduction (Oxford, England)》2001,16(1):148-152
Sperm immobilization prior to intracytoplasmic sperm injection (ICSI) is thought to be necessary for efficient fertilization. A variety of methods of sperm immobilization (pipetting, squeezing and piezo application) are currently employed in ICSI. The effect of differences in immobilization method on the timing of initial Ca(2+) oscillations of oocytes in ICSI was investigated. Motile spermatozoa were immobilized in eosin Y solution using pipetting, squeezing and piezo application. Complete staining of the sperm head was achieved after 220.7, 42.2 and 5.0 s respectively. Oscillations after ICSI were measured fluorometrically for each method. The onset of Ca(2+) oscillations was observed at 4.8 to 80.4 min after ICSI. Ca(2+) oscillations developed earlier with the piezo method (14.4 +/- 6.4 min) than other methods (pipetting, 43.1 +/- 20.2 min, P < 0.01; squeezing, 18.4 +/- 3.8 min, P = NS). The piezo method produced the earliest staining of the sperm head and may have caused the most damage to the sperm membrane. A more rapid onset of Ca(2+) oscillations was also observed with the piezo method. The method of sperm immobilization may be important for the rapid release of sperm factors that initiate oocyte activation. This study also showed that Ca(2+) oscillations develop earlier in human oocytes treated by ICSI than indicated in previous reports. 相似文献