E. Dul | University of Groningen (original) (raw)

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Research paper thumbnail of Can Characteristics of Reciprocal Translocations Predict the Chance of Transferable Embryos in PGD Cycles?

Journal of Clinical Medicine, 2014

Translocation carriers have an increased risk of miscarriage or the birth of a child with congeni... more Translocation carriers have an increased risk of miscarriage or the birth of a child with congenital anomalies. Preimplantation genetic diagnosis (PGD) is performed in translocation carriers to select for balanced embryos and, thus, increase the chance of an ongoing pregnancy. However, a common experience is that reciprocal translocation carriers produce a high percentage of unbalanced embryos, which cannot be transferred. Therefore, the pregnancy rates in PGD in this patient group are low. In a cohort of 85 reciprocal translocation carriers undergoing PGD we have searched for cytogenetic OPEN ACCESS J. Clin. characteristics of the translocations that can predict the percentage of balanced embryos. Using shape algorithms, the most likely segregation mode per translocation was determined. Shape algorithm, breakpoint location, and relative chromosome segment sizes proved not to be independent predictors of the percentage of balanced embryos. The ratio of the relative sizes of the translocated segments of both translocation chromosomes can give some insight into the chance of transferable embryos: Very asymmetrical translocations have a higher risk of unbalanced products (p = 0.048). Counseling of the couples on the pros and cons of all their reproductive options remains very important.

Research paper thumbnail of The prevalence of chromosomal abnormalities in subgroups of infertile men

Human Reproduction, 2012

background: The prevalence of chromosomal abnormalities is assumed to be higher in infertile men ... more background: The prevalence of chromosomal abnormalities is assumed to be higher in infertile men and inversely correlated with sperm concentration. Although guidelines advise karyotyping infertile men, karyotyping is costly, therefore it would be of benefit to identify men with the highest risk of chromosomal abnormalities, possibly by using parameters other than sperm concentration. The aim of this study was to evaluate several clinical parameters in azoospermic and non-azoospermic men, in order to assess the prevalence of chromosomal abnormalities in different subgroups of infertile men. methods: In a retrospective cohort of 1223 azoospermic men and men eligible for ICSI treatment, we studied sperm parameters, hormone levels and medical history for an association with chromosomal abnormalities.

Research paper thumbnail of Chromosomal abnormalities in azoospermic and non-azoospermic infertile men: numbers needed to be screened to prevent adverse pregnancy outcomes

Human Reproduction, 2012

study question: How many infertile men who wish to conceive need to be screened for chromosomal a... more study question: How many infertile men who wish to conceive need to be screened for chromosomal abnormalities to prevent one miscarriage or the birth of one child with congenital anomalies (CAs)?

Research paper thumbnail of Who should be screened for chromosomal abnormalities before ICSI treatment?

Human Reproduction, 2010

Guidelines on karyotyping infertile men before ICSI treatment are not consistent. Most guidelines... more Guidelines on karyotyping infertile men before ICSI treatment are not consistent. Most guidelines recommend chromosomal screening in azoospermic and severe oligozoospermic men, because they are assumed to have the highest risk of abnormalities. We performed a retrospective cohort study in azoospermic men and men eligible for ICSI. We determined the prevalence of chromosomal abnormalities in relation to sperm concentration and compared our data to studies in the literature. A high prevalence of chromosomal abnormalities in azoospermic men was found, but no difference in the prevalence of abnormalities was seen between different sperm concentration categories in non-azoospermic men. This raises the question of who should be screened for chromosomal abnormalities before ICSI treatment. Considering the costs and benefits, we would propose limiting screening to infertile couples with non-obstructive azoospermia.

Research paper thumbnail of Can Characteristics of Reciprocal Translocations Predict the Chance of Transferable Embryos in PGD Cycles?

Journal of Clinical Medicine, 2014

Translocation carriers have an increased risk of miscarriage or the birth of a child with congeni... more Translocation carriers have an increased risk of miscarriage or the birth of a child with congenital anomalies. Preimplantation genetic diagnosis (PGD) is performed in translocation carriers to select for balanced embryos and, thus, increase the chance of an ongoing pregnancy. However, a common experience is that reciprocal translocation carriers produce a high percentage of unbalanced embryos, which cannot be transferred. Therefore, the pregnancy rates in PGD in this patient group are low. In a cohort of 85 reciprocal translocation carriers undergoing PGD we have searched for cytogenetic OPEN ACCESS J. Clin. characteristics of the translocations that can predict the percentage of balanced embryos. Using shape algorithms, the most likely segregation mode per translocation was determined. Shape algorithm, breakpoint location, and relative chromosome segment sizes proved not to be independent predictors of the percentage of balanced embryos. The ratio of the relative sizes of the translocated segments of both translocation chromosomes can give some insight into the chance of transferable embryos: Very asymmetrical translocations have a higher risk of unbalanced products (p = 0.048). Counseling of the couples on the pros and cons of all their reproductive options remains very important.

Research paper thumbnail of The prevalence of chromosomal abnormalities in subgroups of infertile men

Human Reproduction, 2012

background: The prevalence of chromosomal abnormalities is assumed to be higher in infertile men ... more background: The prevalence of chromosomal abnormalities is assumed to be higher in infertile men and inversely correlated with sperm concentration. Although guidelines advise karyotyping infertile men, karyotyping is costly, therefore it would be of benefit to identify men with the highest risk of chromosomal abnormalities, possibly by using parameters other than sperm concentration. The aim of this study was to evaluate several clinical parameters in azoospermic and non-azoospermic men, in order to assess the prevalence of chromosomal abnormalities in different subgroups of infertile men. methods: In a retrospective cohort of 1223 azoospermic men and men eligible for ICSI treatment, we studied sperm parameters, hormone levels and medical history for an association with chromosomal abnormalities.

Research paper thumbnail of Chromosomal abnormalities in azoospermic and non-azoospermic infertile men: numbers needed to be screened to prevent adverse pregnancy outcomes

Human Reproduction, 2012

study question: How many infertile men who wish to conceive need to be screened for chromosomal a... more study question: How many infertile men who wish to conceive need to be screened for chromosomal abnormalities to prevent one miscarriage or the birth of one child with congenital anomalies (CAs)?

Research paper thumbnail of Who should be screened for chromosomal abnormalities before ICSI treatment?

Human Reproduction, 2010

Guidelines on karyotyping infertile men before ICSI treatment are not consistent. Most guidelines... more Guidelines on karyotyping infertile men before ICSI treatment are not consistent. Most guidelines recommend chromosomal screening in azoospermic and severe oligozoospermic men, because they are assumed to have the highest risk of abnormalities. We performed a retrospective cohort study in azoospermic men and men eligible for ICSI. We determined the prevalence of chromosomal abnormalities in relation to sperm concentration and compared our data to studies in the literature. A high prevalence of chromosomal abnormalities in azoospermic men was found, but no difference in the prevalence of abnormalities was seen between different sperm concentration categories in non-azoospermic men. This raises the question of who should be screened for chromosomal abnormalities before ICSI treatment. Considering the costs and benefits, we would propose limiting screening to infertile couples with non-obstructive azoospermia.

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