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1.
Hum Reprod ; 21(4): 852-6, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16339167

RESUMO

In 2004 a law was introduced in The Netherlands, which gives offspring conceived by semen or oocyte donation the right to know the identity of the donor. The law also regulates the provision of other information concerning the donor to the offspring, their parents or their general practitioner. With the introduction of this law, a choice has been made in which the wish of offspring prevails above others involved. Donors can no longer claim absolute anonymity; they are anonymous at the time of donation, but if a child aged > or =16 years requests information the donor may now be traced. During 15 years of debate on the abolition of donor anonymity the number of donors decreased by >70% and the number of semen banks by 50%. We describe the debate which led to the law, the characteristics of the law itself and note some of the probable and possible consequences for donor offspring, parents, donors and semen banks.


Assuntos
Doação de Oócitos/legislação & jurisprudência , Sêmen , Doadores de Tecidos/legislação & jurisprudência , Filhos Adultos/psicologia , Países Baixos , Pais/psicologia , Bancos de Esperma/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/legislação & jurisprudência , Obtenção de Tecidos e Órgãos/tendências
2.
Int J Androl ; 27(3): 140-6, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15139968

RESUMO

The occurrence of DNA breaks in human sperm is of concern to genetic safety in artificial reproduction techniques. Here, we have explored the neutral comet assay (NCA) for evaluating the frequency of spermatozoa with double strand (ds) DNA breaks in normospermic donors. The NCA results into DNA tail formation by fibre extension and by the separation of DNA fragments. Gamma-irradiated native, lysed and lysed plus RNA and protein degraded human sperm nuclei have been used to assess sensitivity and specificity of fragment formation as an indication for ds DNA breaks. At 5 and 10 Gy gamma irradiation, the sensitivity increases in the order: native, lysed, lysed plus RNA and protein degraded. At 10 Gy, a uniform response between donors was obtained. For technical and biological reasons, the NCA underestimates the true incidence of ds DNA breaks by an unknown factor. Semen samples of six healthy normospermic donors were differentiated by swim up and by Percoll density centrifugation, followed by the NCA. In native semen, percentages of sperm nuclei with ds DNA breaks ranged from 15 to 25%. Swim up and selection for high-density sperm nuclei (high Percoll fraction) reduced the frequency of sperm with ds DNA breaks by about one third, whereas an increased frequency was found in the low Percoll fraction. In conclusion, the response to gamma irradiation of DNA fragment formation indicates the NCA to demonstrate ds DNA breaks which is in keeping with theory and experimental results from somatic cells. Ds DNA breaks are a characteristic of the sperm population of normal donors. Current sperm selection procedures reduce the fractions of sperm with ds DNA breaks, yet are not effective in eliminating these cells.


Assuntos
Ensaio Cometa , Dano ao DNA , Fragmentação do DNA/genética , Espermatozoides/efeitos da radiação , Centrifugação com Gradiente de Concentração , Relação Dose-Resposta à Radiação , Raios gama , Humanos , Masculino , Povidona , Sensibilidade e Especificidade , Dióxido de Silício , Motilidade dos Espermatozoides , Espermatozoides/citologia , Espermatozoides/fisiologia
3.
Hum Reprod ; 14(1): 65-9, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10374096

RESUMO

The aim of this prospective study was to evaluate whether couples with total fertilization failure in a previous in-vitro fertilization (IVF) attempt should be offered an additional IVF treatment with elevated insemination concentration or should be treated with intracytoplasmic sperm injection (ICSI). In 23 cycles 228 sibling metaphase II (MII) oocytes were randomly divided: 143 and 85 oocytes were utilized for ICSI and IVF respectively. Of the 143 injected (ICSI) oocytes, 90 (62.9%) were normally fertilized (two pronuclei), whereas 21 (14.7%) oocytes were damaged by the ICSI procedure. Of the fertilized oocytes 72 (80%) developed into transferable embryos. No fertilization at all was observed in the 85 sibling MII oocytes which were inseminated (P < 0.001). In all 23 cycles at least one embryo, obtained by ICSI, could be replaced. Eight pregnancies were achieved of which six resulted in the delivery of nine healthy children. In conclusion, for couples with no or almost no fertilization of oocytes in previous IVF attempts, ICSI appeared to be far superior to an additional IVF attempt with further elevated insemination concentrations.


Assuntos
Fertilização in vitro/métodos , Contagem de Espermatozoides , Adulto , Coeficiente de Natalidade , Citoplasma , Feminino , Fertilização/fisiologia , Humanos , Masculino , Metáfase/fisiologia , Micromanipulação , Taxa de Gravidez , Estudos Prospectivos , Retratamento , Espermatozoides , Falha de Tratamento
4.
Fertil Steril ; 71(4): 690-6, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10202880

RESUMO

OBJECTIVE: To determine whether there is an association between abnormal semen parameters and occupational exposures to organic solvents, metals, and pesticides. DESIGN: Case-control study using three case groups based on different cutoff values for semen parameters and one standard reference group. SETTING: University Hospital Utrecht and University Hospital Rotterdam, the Netherlands. PATIENT(S): Male partners of couples having their first consultation at the two infertility clinics (n = 899). INTERVENTION(S): Men provided at least one semen sample. Occupational exposure was assessed with use of job-specific questionnaires, a job exposure matrix, and measurements of metals and metabolites of solvents in urine. MAIN OUTCOME MEASURE(S): Standard clinical semen analyses were used to define case groups and controls. RESULT(S): An association between aromatic solvents and reduced semen quality was demonstrated, irrespective of the exposure assessment method used. The associations were stronger if the case definition was based on stricter cutoff values for semen parameters. Risk estimates were higher if the analysis was restricted to primary infertile men. Exposure to other pollutants at the workplace was not associated with impaired semen quality. CONCLUSION(S): The findings indicated an association between aromatic solvent exposure and impaired semen parameters.


Assuntos
Infertilidade Masculina/etiologia , Exposição Ocupacional , Sêmen/fisiologia , Adulto , Poluentes Ocupacionais do Ar/efeitos adversos , Cádmio/urina , Estudos de Casos e Controles , Cromo/urina , Poeira/efeitos adversos , Feminino , Humanos , Infertilidade Masculina/fisiopatologia , Masculino , Metais/efeitos adversos , Metais/urina , Praguicidas/efeitos adversos , Fatores de Risco , Fumar/urina , Solventes/efeitos adversos
6.
Hum Reprod ; 13(6): 1553-8, 1998 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9688391

RESUMO

In this randomized crossover trial we investigated whether the use of controlled ovarian hyperstimulation with low-dose human menopausal gonadotrophin in couples with male subfertility leads to a higher probability of conception when intrauterine insemination (IUI) is applied. We also investigated whether the efficacy of IUI in natural or stimulated cycles was related to the severity of male subfertility. Seventy-four couples completed 308 treatment cycles. Thirteen pregnancies occurred after IUI in a natural cycle (pregnancy rate per completed cycle: 8.4%) and 21 after IUI in a stimulated cycle (pregnancy rate per completed cycle: 13.7%). The difference between the two treatment modalities was not statistically significant. The efficacy of IUI in stimulated cycles was related to the severity of the semen defect. In couples with a total motile sperm count < 10 x 10(6), ovarian stimulation did not improve treatment outcome, while it did in couples with a total motile sperm count > or = 10 x 10(6). Compared with the expected chance of conceiving spontaneously without treatment, both natural and stimulated cycles improved the probability of conception. We conclude that, for the group as a whole, ovarian stimulation did not improve the probability of conception. However, in couples with less severe semen defects, ovarian stimulation did improve the probability of conception.


Assuntos
Fármacos para a Fertilidade Feminina/administração & dosagem , Fertilização in vitro/métodos , Infertilidade Masculina , Menotropinas/administração & dosagem , Indução da Ovulação , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gravidez , Taxa de Gravidez , Capacitação Espermática
7.
Biol Reprod ; 58(3): 670-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9510955

RESUMO

Protein C inhibitor (PCI) is a heparin-binding plasma serine protease inhibitor that was originally identified as an inhibitor of activated protein C. PCI has a broad protease specificity, inhibiting several proteases in hemostasis and fibrinolysis by acting as a suicide substrate. Recently it has been reported that proteases of the reproductive system, such as acrosin, prostate-specific antigen, and tissue kallikrein, can also be effectively inhibited by PCI. However, a direct relation between PCI and physiological events during fertilization has not yet been established. An attempt was made to monitor and localize the inhibition of the sperm protease acrosin by PCI. Localization experiments for PCI on epididymal spermatozoa showed that PCI is present on the acrosomal cap of human spermatozoa, which demonstrates the early presence of PCI in the male reproductive tract. Induction of the acrosome reaction in ejaculated human spermatozoa resulted in the disappearance of PCI from the plasma membrane overlying the acrosomal head and the appearance of a strict distribution at the equatorial segment of human spermatozoa. The activity of acrosin in sperm extracts could be effectively inhibited by PCI. Zona-binding assays showed that active PCI is able to block sperm-egg binding in a concentration-dependent manner. The combination of the potent inhibition of acrosin and sperm-egg binding by PCI and the localization studies suggested that PCI may protect spermatozoa against premature acrosome reaction and degradation, thereby modulating the acrosin activity so that it can coincide with binding to the oocyte.


Assuntos
Inibidor da Proteína C/farmacologia , Inibidores de Serina Proteinase/farmacologia , Interações Espermatozoide-Óvulo/efeitos dos fármacos , Acrosina/antagonistas & inibidores , Acrossomo/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Técnicas In Vitro , Masculino , Inibidor da Proteína C/imunologia , Inibidor da Proteína C/metabolismo , Inibidores de Serina Proteinase/imunologia , Inibidores de Serina Proteinase/metabolismo , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo
8.
Ned Tijdschr Geneeskd ; 142(46): 2505-8, 1998 Nov 14.
Artigo em Holandês | MEDLINE | ID: mdl-10028337

RESUMO

Some synthetic chemicals and natural compounds occurring in vegetables or animal food products mimic endogenous hormones, especially oestrogens, or may have a general action of disturbing hormonal status. It is assumed that intrauterine exposure to these compounds may have an adverse effect on development, differentiation and function of the genital organs of the male foetus. In a worldwide discussion a supposed drop in human sperm quality is related to foetal exposure to chemicals with oestrogen activity. Experimental animal evidence suggests that foetal exposure to compounds with oestrogenic activity may influence reproductive capabilities. In addition chemicals such as diethylstilbestrol (DES) in humans and dichlorodiphenyltrichloroethane (DDT) in wildlife influence the reproductive system. There is no conclusive evidence of decreasing semen quality in general.


Assuntos
Anormalidades Induzidas por Medicamentos/epidemiologia , Exposição Ambiental/efeitos adversos , Congêneres do Estradiol/efeitos adversos , Genitália Masculina/anormalidades , Espermatozoides/efeitos dos fármacos , Animais , Genitália Masculina/efeitos dos fármacos , Humanos , Incidência , Masculino , Países Baixos/epidemiologia , Espermatozoides/citologia , Teratogênicos/farmacologia
10.
Maturitas ; 30(2): 113-8, 1998 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-9871905

RESUMO

The age related decrease in female fertility is associated with a decrease in follicle numbers and oocyte quality. Meiotic division errors, mitochondrial DNA mutations and ageing itself have been suggested to play a part in the age associated reduction in oocyte quality. During the past decades several hypothesis have been proposed, trying to explain the underlying mechanisms. However, none of them is yet conclusive. This review will consider the main hypotheses regarding the age related reduction in oocyte quality. This will be reviewed together with recent results of studies analysing a possible relationship between ageing and ovarian ageing. On the basis of our own results and those presented in the literature, it is concluded that ovarian ageing may only be related to specific aspects of general ageing.


Assuntos
Envelhecimento/fisiologia , Fertilidade/fisiologia , Oócitos/fisiologia , Ovário/fisiologia , Aberrações Cromossômicas/etiologia , Transtornos Cromossômicos , Feminino , Humanos , Mitocôndrias/fisiologia , Telômero/fisiologia
11.
Ned Tijdschr Geneeskd ; 141(23): 1138-41, 1997 Jun 07.
Artigo em Holandês | MEDLINE | ID: mdl-9380143

RESUMO

Somatic cells of males with azoospermia or oligozoospermia (sperm density < 20 million sperm cells/ml) were found to contain increased percentages of chromosomal abnormalities. Subfertile males with a normal somatic karyogram were found to have increased rates of aneuploidy in sperm. This creates risks for the offspring after fertilization with intracytoplasmatic sperm injection (ICSI). Certain gene mutations on the Y chromosome cause severe oligo- or azoospermia and will, in case of successful reproduction with ICSI, be transmitted to male offspring in 100% of the cases. The same holds true, irrespective of sex, of mutations responsible for cystic fibrosis. In non-random groups of ICSI pregnancies, higher proportions of de novo sex-chromosomal abnormalities have been found than expected. In addition, there are increased proportions of paternally inherited structural autosomal anomalies. Extrapolation of the findings is not yet possible, however.


Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Fertilização in vitro/métodos , Oligospermia/etiologia , Humanos , Masculino , Microinjeções
12.
Hum Reprod ; 12(4): 752-4, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9159437

RESUMO

An infertile couple was referred for intracytoplasmic sperm injection (ICSI) because of primary infertility and oligoasthenoteratozoospermia (OAT) in the male. It was observed that although the sperm cells presented with an unusual head size and multiple tails they were able to fertilize the oocytes after ICSI. Subsequent molecular cytogenetic analysis demonstrated de-novo chromosome abnormalities in virtually all sperm cells with 40% diploidy and 24% triploidy in addition to aneuploidy for the sex chromosomes.


Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Fertilização in vitro/métodos , Infertilidade Masculina/genética , Interações Espermatozoide-Óvulo , Adulto , Citoplasma , Feminino , Genótipo , Humanos , Hibridização in Situ Fluorescente , Masculino , Microinjeções , Oligospermia/genética , Fenótipo
14.
Fertil Steril ; 66(5): 769-75, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8893683

RESUMO

OBJECTIVE: To investigate the relation between the implantation rate per embryo after replacement in IVF-ET in relation to female age. DESIGN: Retrospective study using linear and biphasic models in a multivariate analysis. SETTING: Academic tertiary care institution. INTERVENTION(S): In vitro fertilization-ET and determination of gestational sacs at 6 to 7 weeks of pregnancy buy ultrasound. MAIN OUTCOME MEASURE(S): Implantation rate as defined by the number of gestational sacs per embryo replaced. RESULT(S): Woman's age and embryo morphology were strongly related to the implantation rate, indication for IVF-ET and cycle rank number also were related significantly but less strongly. A linear model was built describing the decrease in implantation rate with age, resulting in a decrease of approximately 7%. A biphasic model was tested also and performed significantly better, resulting in a yearly decrease of > 20% after 37 years of age. CONCLUSION(S): The most important independent factors related to the ability of embryos to implant are female age and embryo morphology. The best way to describe the relation with female age is biphasic model with a discontinuity at approximately 37 years of age.


Assuntos
Envelhecimento , Implantação do Embrião/fisiologia , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Infertilidade/etiologia , Infertilidade/terapia , Masculino , Análise Multivariada , Gravidez
15.
Int J Androl ; 18 Suppl 2: 72-5, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719863

RESUMO

Using the results of randomized and controlled studies, it was assessed whether there is still a place for intra-uterine insemination (IUI), with or without controlled ovarian hyperstimulation (COH), as a treatment for male subfertility. It is concluded that, in the case of a moderate to severe semen defect, well-timed IUI should be applied in natural cycles only, because COH does not further improve treatment outcome. In contrast, in the case of a mild semen defect, the present evidence indicates that COH improves the probability of conception. If COH is applied, stimulation should be mild in order to prevent multiple pregnancies and the ovarian hyperstimulation syndrome.


Assuntos
Infertilidade Masculina/terapia , Inseminação Artificial , Ensaios Clínicos como Assunto , Humanos , Masculino
16.
Int J Androl ; 18 Suppl 2: 91-3, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8719868

RESUMO

In-vitro fertilization is a successful treatment for infertile couples. However, in a minority of cases it can be dangerous, both for mother and child. IVF should therefore be avoided in (almost) fertile couples. A simple prognostic model makes it possible to distinguish couples with a good chance of conceiving spontaneously from those who deserve treatment in due course. Use of this model should enable IVF to be avoided in (almost) fertile couples.


Assuntos
Fertilização in vitro/efeitos adversos , Infertilidade/terapia , Humanos , Infertilidade/diagnóstico , Masculino , Prognóstico
17.
Fertil Steril ; 63(6): 1172-6, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7750584

RESUMO

OBJECTIVE: To investigate the effect of mild ovarian hyperstimulation on hormonal and sonographic variables of the subsequent natural cycle. DESIGN: Prospective study of three consecutive cycles. SETTING: University Hospital, Department of Reproductive Medicine, Division of Obstetrics and Gynecology. PATIENTS: Twelve couples with subnormal semen as the only identifiable cause of subfertility. INTERVENTIONS: Subjects were offered IUI for three cycles. In the second cycle, mild ovarian hyperstimulation with 75 IU IM hMG was applied daily and ovulation was induced with 5,000 IU hCG. In the first and third both natural cycles, serum samples were obtained for hormone measurements and ultrasound (US) scanning of the ovaries was performed. MAIN OUTCOME MEASURE: To determine whether there was a carryover effect of mild ovarian hyperstimulation as applied in the second cycle, hormone levels and US scans of cycle 3 were compared with those of cycle 1. RESULTS: None of the variables of cycle 3 were significantly different from those of cycle 1. CONCLUSION: Because hormonal and sonographic variables in the subsequent natural cycle remain unchanged, a carryover effect of mild ovarian hyperstimulation with gonadotropins seems unlikely.


Assuntos
Gonadotropina Coriônica/uso terapêutico , Infertilidade Masculina/terapia , Menotropinas/uso terapêutico , Indução da Ovulação , Adulto , Gonadotropina Coriônica/administração & dosagem , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Hormônio Luteinizante/sangue , Masculino , Menotropinas/administração & dosagem , Ovário/fisiologia , Estudos Prospectivos
19.
Andrologia ; 26(6): 323-9, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-7872506

RESUMO

UNLABELLED: The relationship between sperm movement characteristics obtained by computerized analysis and the in vitro fertilization rates of human oocytes was studied. In 144 consecutive in vitro fertilization treatments a sample of prepared semen was analysed by a Hamilton-Thorn Motility Analyzer. In addition a visual estimation of sperm count and motility was made. Significant correlations with the fertilization rate were found for all visual parameters. Of the computerized measurements, the mean velocities of motile spermatozoa and the concentration of motile cells were significantly correlated. The average path velocity correlated best (r = 0.42, P < 0.001). There was no relationship between the percentage of motile sperm showing hyperactivated movement and the fertilization rate. A forward stepwise logistic regression analysis selected the following variables of predictive value for fertilization: average path velocity, male factor infertility as indication for in vitro fertilization, motility and concentration, as measured by the Hamilton-Thorn analyzer. A logistic regression model to predict the cases with low (< 0.2) or high fertilization rates, included the average path velocity as a significant variable and classified the samples with 90% overall accuracy. IN CONCLUSION: movement characteristics of spermatozoa in culture medium, especially the average path velocity are of prognostic value in prediction of human oocyte fertilization rates.


Assuntos
Processamento Eletrônico de Dados , Fertilização in vitro , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Computadores , Humanos , Modelos Logísticos , Masculino , Valor Preditivo dos Testes , Contagem de Espermatozoides
20.
Hum Reprod ; 9(11): 2022-6, 1994 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7868667

RESUMO

In this randomized trial we investigated whether intra-uterine insemination (IUI) in couples with male subfertility leads to a higher probability of conception than timed intercourse after ovarian stimulation with human menopausal gonadotrophin (HMG) and human chorionic gonadotrophin (HCG). A total of 76 couples started 249 cycles, of which 47 were cancelled to prevent multiple pregnancies or hyperstimulation. After 202 completed treatment cycles, 15 pregnancies occurred, 11 after IUI and four after timed intercourse. The pregnancy rate per completed cycle with IUI was 10.3% (95% confidence interval: 5.5-17.5%) and 4.2% (1.2-10.1%) with timed intercourse. Compared with the estimated spontaneous chance to conceive, IUI after ovarian stimulation appeared to be more effective in the first three cycles. We conclude that in subfertile couples with a male factor, IUI tends to improve the probability of conception as compared to timed intercourse when ovarian stimulation is applied, and we advise such treatment for three cycles.


Assuntos
Coito , Infertilidade Masculina/terapia , Inseminação Artificial Homóloga , Indução da Ovulação , Adulto , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Fatores de Tempo
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