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1.
Sci Rep ; 11(1): 3560, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574395

RESUMO

The PolariX TDS (Polarizable X-Band Transverse Deflection Structure) is an innovative TDS-design operating in the X-band frequency-range. The design gives full control of the streaking plane, which can be tuned in order to characterize the projections of the beam distribution onto arbitrary transverse axes. This novel feature opens up new opportunities for detailed characterization of the electron beam. In this paper we present first measurements of the Polarix TDS at the FLASHForward beamline at DESY, including three-dimensional reconstruction of the charge-density distribution of the bunch and slice emittance measurements in both transverse directions. The experimental results open the path toward novel and more extensive beam characterization in the direction of multi-dimensional-beam-phase-space reconstruction.

2.
Reprod Biomed Online ; 30(5): 504-13, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25735918

RESUMO

Bemfola (follitropin alfa) (Finox AG, Switzerland), a new recombinant FSH, has a comparable pharmacological profile to that of Gonal-f (Merck Serono, Germany), the current standard for ovarian stimulation. A randomized, multi-centre, Phase 3 study in women undergoing IVF or intracytoplasmic sperm injection (n = 372) showed Bemfola yielding similar efficacy and safety profiles to Gonal-f. Women aged 20-38 years of age were randomized 2:1 to receive a single, daily, subcutaneous 150 IU dose of either Bemfola or Gonal-f. This study tested equivalence in the number of retrieved oocytes using a pre-determined clinical equivalence margin of ±2.9 oocytes. Compared with Gonal-f, Bemfola treatment resulted in a statistically equivalent number of retrieved oocytes (Bemfola 10.8 ± 5.11 versus Gonal-f 10.6 ± 6.06, mean difference: 0.27 oocytes, 95% confidence interval: -1.34, 1.32) as well as a similar clinical pregnancy rate per embryo transfer in first and second cycles (Bemfola: 40.2% and 38.5%, respectively; Gonal-f: 48.2% and 27.8%, respectively). No difference in severe ovarian hyperstimulation syndrome was observed between treatment groups (Bemfola: 0.8%; Gonal-f: 0.8%). This study demonstrates similar clinical efficacy and safety profiles between Bemfola and Gonal-f, and suggests that Bemfola can be an appropriate alternative in ovarian stimulation protocols.


Assuntos
Fertilização in vitro , Indução da Ovulação/métodos , Feminino , Humanos
3.
Reprod Biomed Online ; 27(1): 81-8, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23665264

RESUMO

Since most current techniques analysing spermatozoa will inevitably exclude these gametes from further use, attempts have been made to enrich semen samples with physiological spermatozoa with good prognosis using special sperm-processing methods. A particular sperm-selection chamber, called the Zech-selector, was found to be effective in completely eliminating spermatozoa with DNA strand breaks. The aim of this study was to further analyse the subgroup of spermatozoa accumulated using the Zech-selector. In detail, the potential of the chamber to select for proper sperm morphology, DNA status and chromatin condensation was tested. Two samples, native and processed semen, of 53 patients were analysed for sperm morphology (×1000, ×6300), DNA packaging (fragmentation, chromatin condensation) and chromosomal status (X, Y, 18). Migration time (the time needed for proper sperm accumulation) was significantly correlated to fast progressive motility (P=0.002). The present sperm-processing method was highly successful with respect to all parameters analysed (P<0.001). In particular, spermatozoa showing numeric (17.4% of patients without aneuploidy) or structural chromosomal abnormalities (90% of patients without strand-breaks) were separated most effectively. To summarize, further evidence is provided that separating spermatozoa without exposure to centrifugation stress results in a population of highly physiological spermatozoa.


Assuntos
Aneuploidia , Separação Celular/métodos , Empacotamento do DNA , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Adulto , Separação Celular/instrumentação , Fragmentação do DNA , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise do Sêmen , Espermatozoides/citologia
4.
Reprod Biomed Online ; 25(3): 267-72, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22796233

RESUMO

Normally, day-2 embryos show a crosswise arrangement of four cells with three blastomeres lying side by side. Cleavage anomalies include embryos that are characterized by a particular planar constellation of four blastomeres with presumed incomplete cleavage. Since little is known on the developmental fate of such conceptuses, within a 10-month period all consecutive patients were screened for day-2 planar embryos. A total of 64/2070 embryos with suboptimal blastomere configuration were detected (3.1%). In conventional IVF, planar embryos were significantly less frequent (0.7%) as compared with intracytoplasmic sperm injection (2.8%; P<0.05) and cases of testicular sperm extraction (5.4%; P<0.01). Interestingly, embryos with a cleavage anomaly showed better morphology both on day 2 (P<0.005) and day 3 (P<0.001). In contrast, blastocyst formation (P<0.001) and blastocyst quality (P=NS) was higher in tetrahedral embryos. There was a significant increase in implantation rate if tetrahedral embryos could be transferred compared with when planar embryos had to be transferred (P<0.01). It may be postulated that, in planar embryos, the mitotic spindle might have been affected, e.g. sperm centrosome composition or function, which in turn might have led to the observed cleavage anomaly. Normally, day-2 embryos show a crosswise arrangement of four cells with three blastomeres lying side by side. Cleavage anomalies include more planar embryos that are characterized by a particular flat constellation of four blastomeres with presumed premature cleavage (like a tetrafoliate clover). Since little is known on the developmental fate of such embryos within a 10-month study period, all consecutive patients were screened for the presence of day-2 planar embryos (study group). A total of 64 (out of 2070) embryos with abnormal blastomere configuration were detected (3.1%). Interestingly, in conventional IVF (0.7%), the presence of planar embryos was significantly less frequent as compared with intracytoplasmic sperm injection (2.8%; P<0.05) and cases of testicular biopsy (5.4%; P<0.01). Embryos from the study group showed better morphology both on day 2 (P<0.005) and day 3 (P<0.001). In contrast, blastocyst formation (survival to day 5 of preimplantation development) was higher in the normally cleaved control group (P<0.001) and so was blastocyst quality; however, the latter parameter did not reach level of significance. This was also reflected in a significantly higher implantation rate in the control group (P<0.01). Based on present data, it may be postulated that, in planar embryos, the mitotic spindle (which involves the sperm centrosome) might have been affected, which in turn might have led to an incomplete cleavage.


Assuntos
Blastocisto/citologia , Embrião de Mamíferos/patologia , Adulto , Blastômeros/ultraestrutura , Centrossomo/ultraestrutura , Meios de Cultura/farmacologia , Células do Cúmulo/citologia , Implantação do Embrião , Transferência Embrionária , Feminino , Fertilização in vitro/métodos , Humanos , Masculino , Oócitos/citologia , Prognóstico , Estudos Prospectivos , Fuso Acromático , Resultado do Tratamento
5.
Andrologia ; 44 Suppl 1: 2-19, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22211911

RESUMO

Intracytoplasmic sperm injection (ICSI) can be considered the most 'revolutionary' in vitro insemination technique because it has efficiently allowed the treatment of male factor infertility. Although ICSI has been successfully and safely applied worldwide for almost 20 years, currently, we have no real knowledge regarding the hypothetical long-term side effects on ICSI adults, given the increased likelihood of spermatozoa with defective nuclear content fertilising the oocytes. The aim of this review article is to investigate the most recent advances of performing ICSI in the safest possible manner, thus, minimising the theoretical hazards of this procedure. To allow for substantiated recommendation which male gametes to choose for physiological ICSI an updated search was performed in Medline and Embase, from 1996 to June 2011. Recent technical advances allow operators to more or less simulate physiological conditions in the laboratory, reducing potential damage to the gametes. It seems possible to prevent fertilisation by DNA-damaged and chromosomal-unbalanced spermatozoa by selecting ICSI sperm by motility and/or maturation markers such as hyaluronic acid or other zona pellucida receptors. Furthermore, novel non-invasive imaging techniques can be valid tools for helping in the morphological selection of ICSI spermatozoa.


Assuntos
Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas/métodos , Fragmentação do DNA , Humanos , Ácido Hialurônico/metabolismo , Masculino , Interações Espermatozoide-Óvulo , Resultado do Tratamento , Zona Pelúcida
6.
Reprod Biomed Online ; 22(1): 37-43, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21115273

RESUMO

Sperm DNA fragmentation is increased in poor-quality semen samples and correlates with failed fertilization, impaired preimplantation development and reduced pregnancy outcome. Common sperm preparation techniques may reduce the percentage of strandbreak-positive spermatozoa, but, to date, there is no reliable approach to exclusively accumulate strandbreak-free spermatozoa. To analyse the efficiency of special sperm selection chambers (Zech-selectors made of glass or polyethylene) in terms of strandbreak reduction, 39 subfertile men were recruited and three probes (native, density gradient and Zech-selector) were used to check for strand breaks using the sperm chromatin dispersion test. The mean percentage of affected spermatozoa in the ejaculate was 15.8 ± 7.8% (range 5.0­42.1%). Density gradient did not significantly improve the quality of spermatozoa selected(14.2 ± 7.0%). However, glass chambers completely removed 90% spermatozoa showing strand breaks and polyethylene chambers removed 76%. Both types of Zech-selectors were equivalent in their efficiency, significantly reduced DNA damage (P < 0.001) and,with respect to this, performed better than density gradient centrifugation (P < 0.001). As far as is known, this is the first report ona sperm preparation technique concentrating spermatozoa unaffected in terms of DNA damage. The special chambers most probably select for sperm motility and/or maturity.


Assuntos
Separação Celular/instrumentação , Quebras de DNA , Preservação do Sêmen/instrumentação , Bancos de Esperma/métodos , Espermatozoides , Adulto , Separação Celular/métodos , Vidro , Humanos , Infertilidade Masculina , Masculino , Polietileno , Análise do Sêmen , Preservação do Sêmen/métodos , Espermatozoides/citologia , Espermatozoides/fisiologia
7.
Reprod Biomed Online ; 21(6): 762-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21051291

RESUMO

This prospective study tested a new type of culture dish for the effects of individual culture and autotrophic factors. Within a 6-month period, 72 patients with nine or more fertilized eggs were enrolled in this prospective evaluation. Their 936 zygotes were split into three subgroups (individual culture, individual culture with contact to neighbours, group culture). All concepti were cultured in 30 µl drops (medium change on day 3) until blastocyst stage. On day 5, a single-blastocyst transfer was performed and the remaining blastocysts of good quality were vitrified. Fertilization rates were 69% for IVF and 81% for intracytoplasmic sperm injection. Blastulation was 48%. Single-blastocyst transfer resulted in a clinical pregnancy rate of 54%. Group culture was superior in terms of compaction (P<0.01) and blastulation (P<0.001) as compared with individual culture. A better blastocyst quality was observed in group culture (P<0.05). As a trend, more life births were achieved with blastocysts derived from group culture. As far as is known, this is the first evidence that grouping embryos improves preimplantation development in human and it is recommended that culture volume should be reduced or embryo density increased.


Assuntos
Blastocisto/fisiologia , Técnicas de Cultura Embrionária/métodos , Implantação do Embrião/fisiologia , Transferência Embrionária , Zigoto/crescimento & desenvolvimento , Feminino , Humanos , Nascido Vivo , Gravidez , Estudos Prospectivos
8.
Reprod Biomed Online ; 19(1): 72-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19573294

RESUMO

Although some post-thaw morphological predictors of pregnancy have been investigated in slow freezing of blastocysts, no such data have been published for vitrified and warmed blastocysts. Therefore, a prospective four-part score was applied to vitrified/warmed day-5 embryos to evaluate whether certain morphological parameters could serve as predictors of implantation, pregnancy and live birth. All morulae/blastocysts that were considered to be viable after warming were scored according to a previously unpublished grading system based on re-expansion, hatching (out of an artificial gap in the zona pellucida), extensive cytoplasmic granulation and presence of necrotic foci. Overall, 74% (202/273) of the vitrified concepti were found to be viable after warming. Early blastocysts showed better survival versus extended/hatching blastocysts (P < 0.01). Of the morphological parameters analysed, immediate re-expansion (P < 0.05) and hatching (P < 0.001) were positive predictors of the rates of implantation, pregnancy and live birth. The opposite holds for extensive cytoplasmic granulation (P < 0.05), which was negatively related. Accurate scoring of warmed blastocysts (within the first 2 h) allows for prediction of pregnancy outcome, and thus will help to further reduce the number of transferred embryos.


Assuntos
Coeficiente de Natalidade , Implantação do Embrião , Transferência Embrionária , Taxa de Gravidez , Adulto , Feminino , Temperatura Alta , Humanos , Gravidez
9.
Minerva Ginecol ; 61(2): 141-52, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19255561

RESUMO

Artificial reproductive techniques (ART) have become a routine and successful treatment of infertility. Twin pregnancies are more frequent after ART compared to spontaneous conception. Varying findings have been reported for the obstetric and perinatal outcome of ART twin pregnancies as compared to spontaneously conceived twin pregnancies. To evaluate the specific risks of twin pregnancies achieved through ART, literature has been reviewed for obstetric and perinatal risks and differences between artificially and spontaneously conceived twin pregnancies. Eleven studies have been involved in this review. Three of the studies were matched and eight were non-matched studies. Results of analysed studies differed widely. Twin pregnancies resulting from ART showed an increased rate of Caesarean section and tend toward higher risk for preterm birth and low birthweight compared to spontaneously conceived twin pregnancies. Various conditions can influence twin pregnancies outcome after ART. In in-vitro fertilization programs twin pregnancies should be avoided and physicians have to inform patients of the specific risks when transferring more than one embryo.


Assuntos
Técnicas de Reprodução Assistida , Gêmeos , Áustria/epidemiologia , Cesárea/estatística & dados numéricos , Transferência Embrionária/efeitos adversos , Medicina Baseada em Evidências , Feminino , Fertilização in vitro/efeitos adversos , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Idade Materna , Gravidez , Resultado da Gravidez , Redução de Gravidez Multifetal , Nascimento Prematuro/epidemiologia , Técnicas de Reprodução Assistida/efeitos adversos , Fatores de Risco
10.
Reprod Biomed Online ; 18(1): 61-6, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19146770

RESUMO

In terms of treatment outcome, little prognostic power is attributed to day-4 morphology. A day-4 score was applied to 56 patients separating non-compacting embryos from compacting (some areas of compaction) and fully compacted embryos. The latter were further subdivided according to the morphology of compaction. Grade C1 embryos represented optimal quality, while grades C2 (exclusion of fragments) and C3 (exclusion of blastomeres) were characterized by a loss of cytoplasm. Grade 4 embryos (C4) showed incomplete compaction with several blastomeres not yet incorporated into cell mass. Pooled embryos without compaction showed a reduced (P < 0.001) blastulation (28.8%) as compared with compacting embryos with the same cell number (68.8%), which, in turn, revealed lower (P < 0.05) rates of blastulation as compared with concepti that completed compaction process (84.6%). Among fully compacted embryos grade C1 had a better (P < 0.01) blastocyst formation rate (94.4%) as compared with grade C3 (68.2%). Grade C1 embryos showed significantly higher rates of top-quality blastocysts as compared with grade C2 (P < 0.05) and C3 (P < 0.01). Blastocysts deriving from grade C1/C4 embryos led to a higher pregnancy rate as compared with the C2/C3 counterparts (P < 0.05). This modified score allows for adequate prediction of both blastocyst formation/quality and pregnancy.


Assuntos
Embrião de Mamíferos/citologia , Infertilidade/diagnóstico , Infertilidade/terapia , Injeções de Esperma Intracitoplásmicas , Adulto , Blastômeros/citologia , Fase de Clivagem do Zigoto/citologia , Fase de Clivagem do Zigoto/fisiologia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Gravidez , Taxa de Gravidez , Prognóstico , Estudos Retrospectivos , Injeções de Esperma Intracitoplásmicas/métodos
11.
Reprod Biomed Online ; 16(6): 801-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18549689

RESUMO

Assessment of oocyte maturity and quality (morphological appearance) at the time of retrieval is difficult as the egg is obscured by a large cumulus mass that hinders adequate scoring. Since no data are available on the possible relationship between the cumulus-oocyte complex (COC) and oocyte morphology, this prospective intracytoplasmic sperm injection study was set up in 87 consecutive patients. COC were grouped according to expansion of both corona radiata and cumulus matrix. Special emphasis was placed on recording morphological anomalies of COC (inclusion of blood clots and amorphous clumps). For all mature ovae, quality was assessed and preimplantation development followed up to blastocyst stage if fertilized. The risk of not harvesting an oocyte was higher in COC with blood clots compared with normal cumulus matrices (P = 0.004). COC expansion did not allow for prediction of either nuclear status or quality of the egg. The presence of blood clots within the cumulus matrix was associated with reduced oocyte quality (dense central granulation), fertilization rate and blastocyst formation, compared with unaffected COC (P < 0.05). It may be postulated that COC showing blood inclusions derive from poor quality follicles, which has a detrimental effect on oocyte quality and further cleavage to blastocyst stage. Consequently, mechanical removal of blood clots cannot rescue the corresponding embryo.


Assuntos
Células do Cúmulo/patologia , Oócitos/citologia , Trombose/patologia , Adulto , Desenvolvimento Embrionário/fisiologia , Feminino , Humanos , Oócitos/fisiologia , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas
12.
Hum Reprod ; 23(1): 62-6, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17977865

RESUMO

BACKGROUND: Irregularities in composition, thickness and/or color of the zona pellucida may impair optimal function and result in reduced outcome. Anomalies of oocyte shape have not been investigated in detail in this respect. METHODS: Therefore, all patients attending our clinic within a period of 1 year were screened for the presence of ovoid gametes and the corresponding developmental potential was evaluated. For all elongated gametes, a roundness index (RI; length divided by width) was calculated in order to quantify shape. RESULTS: RI did not affect fertilizability (P > 0.05). The degree of dysmorphism was found to be related to cleavage pattern. The more ovoid a gamete was, the higher was the risk of the corresponding zygote not cleaving like a tetrahedron (P < 0.01). Abnormal cleavage (a rather flat array of blastomeres) was associated with delayed compaction (P < 0.01) and blastocyst formation (P < 0.001). The quality of blastocysts was not affected at any stage in ovoid concepti (P > 0.05). CONCLUSIONS: Ovoid oocytes with abnormal cleavage pattern show delayed preimplantation development, probably due to a reduced number of cell-to-cell contacts.


Assuntos
Blastocisto/fisiologia , Forma Celular , Desenvolvimento Embrionário , Oócitos/citologia , Oócitos/fisiologia , Adulto , Fase de Clivagem do Zigoto , Feminino , Fertilização , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco , Injeções de Esperma Intracitoplásmicas , Fatores de Tempo , Zigoto/fisiologia
13.
Artigo em Alemão | MEDLINE | ID: mdl-17272931

RESUMO

Multiple pregnancies following an assisted reproduction technique (ART) should be seen as a complication, and for that reason they should be avoided. In contrast to singleton pregnancies following ART, the multiple pregnancies are associated with a higher prenatal, neonatal and maternal risk; furthermore this results in a financial burden for the health care system. This paper gives an overview of the latest literature and different attempts of European countries, trying to reduce the multiple pregnancy rate. An efficient reduction is only possible by single-embryo transfers. There should be strict and cross-national regulation for the choice of women who should have a transfer of more than one embryo.


Assuntos
Gravidez de Alto Risco , Gravidez Múltipla , Técnicas de Reprodução Assistida/efeitos adversos , Transferência Embrionária , Feminino , Humanos , Recém-Nascido , Cooperação Internacional , Guias de Prática Clínica como Assunto , Gravidez , Resultado da Gravidez , Gêmeos
14.
Hum Reprod ; 21(11): 2972-7, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16835216

RESUMO

BACKGROUND: Granulosa cells are essential mediators of oocyte maturation and fertilization. Because of the denudation of oocytes in preparation for ICSI, any potential positive effect of surplus cumulus cells (CCs) on further development would be unable to exert further effect. In order to evaluate the actual influence of adhering cumulus cells on further preimplantation development, this prospective study was carried out. METHODS: Sibling cumulus-oocyte complexes for 57 ICSI patients were split into a study group (incomplete denudation, n = 314) and a control group (complete denudation, n = 336). According to the cumulus cell pattern after partial denudation, mature gametes from the study group were further subdivided into type A oocytes, which showed several prominent CC clusters (n = 202), and type B (n = 75), which showed a more homogeneous pattern with CC covering the whole surface of the gamete. RESULTS: In immature oocytes, presence of adhered CCs led to a significant increase in resumption of meiosis (P < 0.01). Fertilization rate (P < 0.05) and ability to cleave (P < 0.01) was impaired in the study group, because of difficulties in ICSI of type B oocytes. By contrast, embryo morphology on days 2 (P < 0.01) and 3 (P < 0.05), as well as blastocyst formation, was better (P < 0.05) in the study group (55 blastocysts out of 88 zygotes) as compared to that in the control group (49/105). CONCLUSION: These data indicate that co-culture of oocytes with attached CCs may enhance preimplantation development.


Assuntos
Blastocisto/fisiologia , Oócitos/citologia , Injeções de Esperma Intracitoplásmicas/métodos , Desenvolvimento Embrionário , Feminino , Humanos , Indução da Ovulação , Gravidez , Resultado da Gravidez , Coleta de Tecidos e Órgãos/métodos
15.
Hum Reprod ; 21(8): 2022-6, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16679324

RESUMO

BACKGROUND: Serum anti-Müllerian hormone (AMH) levels provide a powerful means for predicting ovarian response, which is reflected not only by the size of the primordial follicle pool but also by the quality of the oocytes. Considering a mutual interdependence between AMH-expressing somatic cells and gametes, this prospective morphological study was set up to evaluate whether extreme AMH levels represent diminished oocyte quality and developmental incompetence. METHODS: A total of 141 consecutive ICSI patients were subdivided into three groups using the 25th and 75th percentiles of the serum AMH levels (cycle day 3). In these three groups, morphology of all oocytes and fertilization rate, embryo quality and blastocyst formation were evaluated, and FSH, LH and estradiol (E(2)) levels were also measured. RESULTS: Cycle cancellation rate was correlated with AMH levels (P < 0.05). AMH groups 1 (<1.66 ng/ml) and 3 (>4.52 ng/ml) showed oocytes of lower quality [dark central granulation, aggregation of smooth endoplasmic reticulum (sER)] compared with the median group 2 (1.66-4.52 ng/ml). Basal serum FSH did not allow for adequate prognosis in terms of gamete appearance. Fertilization and further cleavage up to blastocyst stage was not affected by AMH levels. CONCLUSIONS: AMH seems to be superior to FSH in predicting both oocyte number and quality.


Assuntos
Glicoproteínas/sangue , Oócitos/citologia , Hormônios Testiculares/sangue , Adulto , Envelhecimento , Hormônio Antimülleriano , Feminino , Humanos , Indução da Ovulação/métodos , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas
16.
Hum Reprod Update ; 11(4): 425-35, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15817523

RESUMO

Recently, one laser system has been introduced in IVF fulfilling all safety requirements, while achieving a high standard of reproducibility in terms of ablation diameter. This 1.48 microm wavelength indium-gallium-arsenic-phosphorus (InGaAsP) semiconductor laser offers a variety of laser applications to the embryologist. On the one hand, zona pellucida of oocytes or embryos can be manipulated in order to facilitate ICSI or biopsy and assist hatching, and on the other, spermatozoa may be paralysed or immobilized prior to usage. To conclude, the 1.48 microm diode laser provides a promising tool for the microdissection of subcellular targets. The diode laser stands out due to the rapidity, the simplicity and the safety of the procedure which is supported by healthy offspring after laser application.


Assuntos
Fertilização in vitro/instrumentação , Lasers , Microdissecção/instrumentação , Animais , Humanos
18.
Hum Reprod ; 19(8): 1837-41, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15166130

RESUMO

BACKGROUND: Complete fertilization failure after ICSI is a rare event, and it may happen repeatedly even in cases of normal sperm parameters and good ovarian response. In these cycles, alternative ICSI techniques may prove useful. METHODS: Our modified ICSI (mICSI) is characterized by aspiration close to the opposite membrane (the region of the mitochondria with a high inner mitochondrial membrane potential) which is followed by central deposition of the sperm. The method was applied prospectively to ICSI cycles of patients with a history of complete fertilization failure in previous ICSI cycles. In parallel, mICSI was compared with conventional ICSI in terms of further preimplantation development and treatment outcome. RESULTS: In patients with previous ICSI failures using conventional ICSI (no 2Pn zygotes out of 70 oocytes that had been injected) application of mICSI led to adequate fertilization (53.6%) and pregnancy rates (33.3%) (P < 0.001; P < 0.01). In patients without previous failed fertilization, no improvement in the rates of fertilization, blastocyst formation, implantation or clinical pregnancy could be seen. CONCLUSIONS: Our data indicate that the present version of ICSI is a reliable alternative to conventional ICSI. However, although it overcomes oocyte-dependent activation failure, routine application does not improve the overall results.


Assuntos
Microinjeções/métodos , Oócitos/fisiologia , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Feminino , Fertilização , Humanos , Infertilidade Masculina , Masculino , Mitocôndrias/fisiologia , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Zigoto/fisiologia
19.
Hum Reprod ; 19(3): 573-8, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14998954

RESUMO

BACKGROUND: In MII oocytes showing difficult oolemma breakage, ICSI can cause an increase in the degeneration rate. This may be overcome by laser-assisted ICSI using a 5-10 micro m opening in the zona pellucida for injection. However, such a small opening might impair the hatching process, especially if assisted hatching is applied in addition. In order to prevent this, the present study used routine injection through an area of zona pellucida in which laser zona thinning had been applied, providing for both a reduced mechanical stress to the oocyte and assisted hatching. METHODS: This prospective study involved 100 cycles with 1016 MII oocytes. Conventional ICSI (control group) was compared with a modified laser-assisted ICSI (study group) in sibling oocytes. In the latter group oocytes were injected through an extended area of zona thinning. RESULTS: Degeneration rate was significantly lower in the study group (P < 0.004). There were no differences in fertilization, or formation and quality of blastocysts. In the study group embryo quality on day 2 was significantly better (P = 0.004) and herniation of day 5 blastocysts was increased (P = 0.005). Rates of implantation and pregnancy were not affected. However, on day 3 laser-assisted ICSI proved beneficial (P = 0.038) in terms of clinical pregnancy rate. CONCLUSIONS: The new method combines a less invasive ICSI technique with assisted hatching. Our preliminary data indicate that in addition to an improved oocyte survival, this new approach increases the hatching rate in vitro, which may explain the increase in pregnancy rate, at least in day 3 transfers.


Assuntos
Lasers , Injeções de Esperma Intracitoplásmicas/métodos , Zona Pelúcida/efeitos da radiação , Adulto , Blastocisto/fisiologia , Sobrevivência Celular/efeitos da radiação , Implantação do Embrião , Embrião de Mamíferos/fisiologia , Feminino , Humanos , Oócitos/fisiologia , Gravidez , Taxa de Gravidez , Resultado do Tratamento
20.
Hum Reprod ; 18(11): 2406-12, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14585894

RESUMO

BACKGROUND: Since there is considerable disagreement in grading cytoplasmic haloes, this prospective study was set up to evaluate if certain subtypes of haloes are related to further development. METHODS: Out of a total of 152 patients, 713 zygotes could be checked for the formation of a halo. Where present, haloes were subdivided into concentric (symmetric) and polar (asymmetric) types. In addition, each halo was measured accurately to see if the extension of the halo might influence further development. In parallel, pronuclear patterns were checked. RESULTS: Halo-positive zygotes did not differ from halo-negative ones in terms of embryo quality and blastocyst formation rate. However, quality of blastocysts (assessed by their inner cell mass consistency) was significantly increased (P < 0.001) if a halo appeared at zygote stage. This phenomenon was not related to type of halo or degree of halo. In terms of pronuclear pattern, pattern 0 (0A, 0B) led to significantly more blastocysts (P < 0.001) of better quality (P = 0.002) compared with patterns 1-5. A stepwise logistic regression showed no relationship between different halo types and pronuclear pattern 0. CONCLUSIONS: The present study indicates that any halo has a positive prognostic value on blastocyst quality, irrespective of the fact that it is light or extreme, polar or concentric. In addition, the developmental advantage of pattern 0 is confirmed.


Assuntos
Blastocisto/fisiologia , Citoplasma/ultraestrutura , Fertilização in vitro , Injeções de Esperma Intracitoplásmicas , Zigoto/ultraestrutura , Adulto , Blastocisto/citologia , Fase de Clivagem do Zigoto , Estudos de Coortes , Implantação do Embrião , Feminino , Humanos , Modelos Logísticos , Gravidez , Taxa de Gravidez , Prognóstico , Estudos Prospectivos
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