Numerical chromosome anomalies detected in paternally derived pronuclei of tripronuclear zygotes after intracytoplasmic sperm injection.
OBJECTIVE
To investigate after intracytoplasmic sperm injection (ICSI) the paternal-derived pronuclei of zygotes with three pronuclei (3PN) for numerical-chromosome anomalies by using fluorescence in situ hybridization.


METHODS
A total of 211 ICSI 3PN zygotes have been analyzed for numerical-chromosome anomalies in paternally derived pronuclei and compared with the group of 82 zygotes originated during IVF. In the ICSI group, 163 zygotes were evaluated for numerical-chromosome anomalies by using DNA probes for chromosomes 18, X, and Y, and 48 zygotes, for chromosomes 21, X, and Y. In the IVF group, 68 zygotes were evaluated for numerical-chromosome anomalies by using probes for chromosomes 18, X, and Y, and 14 zygotes, by using chromosomes 21, X, and Y.


METHODS
Tripronuclear zygotes were obtained from 74 and 176 patients participating in IVF and ICSI treatment cycles at a university hospital in Switzerland.


METHODS
To evaluate the frequency of numerical-chromosome anomalies in different populations of infertile patients, a total of 211 ICSI zygotes were divided into three groups of zygotes from men with oligozoospermia (n = 124), severe oligozoospermia (n = 53), and azoospermia (n = 34).


METHODS
Incidence of sex-chromosome aneuploidy, diploidy, and aneuploidy for chromosomes 18 or 21.


RESULTS
Overall incidence of numerical-chromosome anomalies in paternal-derived pronuclei after ICSI (9.5%) was significantly higher than the rate found in paternal-derived pronuclei of IVF zygotes (1.2%). Among ICSI zygotes, sex-chromosome aneuploidy (5.2%) and diploidy (2.8%) were two dominant numerical anomalies in paternal-derived pronuclei. In contrast, aneuploidy for autosomes 18 or 21 was not significantly different when comparing ICSI with IVF zygotes. Regarding different groups of infertile patients, the highest incidence of numerical-chromosome anomalies was found in zygotes originating from men with severe oligozoospermia (13.2%), followed by those originating from men with azoospermia (8.8%) and oligozoospermia (8.1%).


CONCLUSIONS
Sex-chromosome aneuploidy and diploidy were the most frequent numerical-chromosome anomalies found in paternal pronuclei of ICSI 3PN zygotes. Surprisingly, no statistically significant difference in the incidence of numerical-chromosome anomalies was observed in the three groups of pronuclei derived from men with oligozoospermia, severe oligozoospermia, and azoospermia.
Macas
Ervin
E
Clinic of Endocrinology, Department of Gynaecology and Obstetrics, University Hospital Zurich, Zurich, Switzerland. ervin.macas@usz.ch
Zweifel
Claire
C
Imthurn
Bruno
B
D000328:Adult; D002467:Cell Nucleus / Q000235:genetics*; D002869:Chromosome Aberrations / Q000706:statistics & numerical data*; D002877:Chromosomes, Human / Q000235:genetics*; D005220:Fathers / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D015994:Incidence; D007248:Infertility, Male / Q000453:epidemiology* / Q000235:genetics / Q000628:therapy*; D008297:Male; D018570:Risk Assessment / Q000379:methods; D012307:Risk Factors; D020554:Sperm Injections, Intracytoplasmic / Q000706:statistics & numerical data*; D013557:Switzerland / Q000453:epidemiology; D015053:Zygote / Q000502:physiology*