Cytogenetic Analysis of Sperm Nucleous Components of Iranian Normal and Sub-Fertile Individuals Using Zona Free Hamster Oocytes

Purpose: The purpose of this study was to investigate whether infertility is affected by sperm chromatin and cytogenetic abnormalities. To this purpose, the frequency of sperm premature chromosome condensation (PCC) induction and numerical chromosome abnormalities in the sperm of normal and sub-fertile men were analyzed. PCC rate was studied for evaluating the role of sperm chromatin abnormalities in the process of nuclear decondensation.Design: Controlled prospective study.Setting: Infertility Genetics Department, Royan Institute.Patient: Sub-fertile males who were referred for infertility treatment and sperm cytogenetical studies.Methods: Hamster oocytes were retrieved after super ovulation by PMSG and HCG injection. Following treatment with Hyaloronidase, zona was removed by trypsin digestion. Sperms were classified according to the morphology, movement and counts and then processed by swim up method. After capacitation, zona-free oocytes were incubated with sperms, and then transferred to fresh media containing colcemid. Slides were prepared using Tarkowskies standard air-drying technique. Oocytes were analyzed using × 1000 microscope after staining in 5% of Giemsa.Main outcome measure: The incidence of sperm aneuploidy, PCC and penetration rate in three groups were determined.Results: Regarding the PCC rate, a significantly higher frequency was found in infertile patients. (P<0.001). The frequency of PCC in oligosperm samples was 36% compared to 19.37% in normal group. A higher frequency of numerical chromosome abnormalities was found in infertile patients. The rate of these abnormalities was 5.6% in normal group and 18.5% in oligospermic samples. Despite the considerable difference between those frequencies, this difference is not significant. (P>0.05)Conclusions: From the results it can be concluded that, formation of sperm PCC is a major cause of failed fertilization in individuals with sperm abnormalities. PCC may form due to chromatin abnormalities, improper DNA packing, chromosomal abnormalities and penetration delay of sperm. Also this may be involved in the etiology of some cases of idiopathic infertility. About numerical chromosome abnormalities although the differences are not significant, there is an association between sperm numerical chromosome abnormalities and male infertility. These abnormalities can be originated from meiotic process in spermatogenesis.     

Cytogenetic analysis of uncleaved oocytes after intracytoplasmic sperm injection

Purpose This work analyzes the causes of cleavage failure after intracytoplasmic sperm injection (ICSI) and the effect of the procedure on the chromosomes of the oocytes.Methods Ninety-seven uncleaved oocytes from 39 patients with severe male infertility or repeated IVF failure were fixed; 79 were analyzable. We checked the decondensation stage of spermatozoa nucleus and the chromosomal abnormalities of the oocytes.Results Among the fixed oocytes, the spermatozoa nucleus was present in 97% of the cases, and it was undecondensed in 89% of the cases, showing no evolution at all. A low rate (2.6%) of premature chromosome condensation (PCC) of the spermatozoa and a low rate (2.5%) of female diploïdy were observed. Among the oocytes that could be karyotyped, we observed a high rate (45%) of chromosome breakage.Conclusion ICSI fertilization failure was due mostly to the complete lack of evolution of the spermatozoa nucleus. Oocyte selection before ICSI seemed to lower the PCC rate. The high rate of oocyte chromosomal breakage rate has to be confirmed.     

Meiotic errors in human oogenesis and spermatogenesis

Chromosome anomalies are extraordinarily common in human gametes, with approximately 21% of oocytes and 9% of spermatozoa abnormal. The types of abnormalities are quite different since most abnormal oocytes are aneuploid, whereas the majority of abnormalities in spermatozoa are structural. Chromosomes 21 and 22 (the smallest chromosomes) are over-represented in aneuploid gametes in both oocytes and sperm. Chromosome 16 is also frequently observed in aneuploid oocytes, whereas the sex chromosomes are particularly predisposed to non-disjunction in human sperm. Maternal age is clearly the most significant factor in the aetiology of aneuploidy; theories about the cause of the maternal age effect are discussed. Paternal age does not have a dramatic effect on the frequency of aneuploid sperm; there is some evidence for a modest increase in the frequency of sex chromosomal aneuploidy. Meiotic recombination has a significant effect on the genesis of aneuploidy in both females and males. New techniques, which allow the analysis of recombination along the synaptonemal complex, have yielded interesting new information in healthy and infertile individuals. There is a link between infertility and the genesis of chromosome abnormalities. Future studies will unravel more of the underlying causal factors.     

How safe is germinal vesicle stage oocyte rescue? Aneuploidy analysis of in vitro matured oocytes

OBJECTIVE: To evaluate the rate and type of aneuploidies of chromosomes 13, 16, 18, 21 and 22, with respect to the length of in vitro maturation (IVM) period, and to compare the results to previously published studies on aneuploidy rates of unfertilized, uninseminated mature oocytes and first polar bodies. STUDY DESIGN: Two hundred and twelve immature germinal vesicle stage oocytes were assigned to two groups. After successful IVM, depending on their maturational period of 24h (Group A) or 36h (Group B), chromosomal analysis was performed by five color fluorescence in situ hybridization (FISH). In Groups A and B the rates of aneuploid oocytes were calculated and compared by chi-square test. Also the rates of hyperhaploidy, hypohaploidy, disomy and nullisomy were determined and compared by chi-square test. The difference was considered statistically significant at p-value of <0.05. RESULTS: The prolonged IVM did not significantly affect the aneuploidy rate compared to the shorter maturation period (48.1% and 45.0%, respectively). Regarding the unbalanced premature chromatid separation, no statistically significant difference was found between hyperhaploidy and hypohaploidy (14.8% versus 8.3%). For chromosome nondisjunction, higher frequency of disomy than nullisomy was observed (30.6% versus 14.8%; p<0.05). The estimated global aneuploidy rate was between 42% and 63%. CONCLUSIONS: The aneuploidy rate of IVM GV-oocytes is comparable to the aneuploidy rate of in vivo matured oocytes and first polar bodies, regardless of the length of maturation period. This suggests that the immature oocytes can be used in infertility treatment after they complete maturation.     

High frequency of de novo DAZ microdeletion in sperm nuclei of subfertile men: possible involvement of genome instability in idiopathic male infertility

The occurrence and diagnosis of Y-chromosome microdeletions, specifically deletions of the DAZ (Deleted in Azoospermia) genes are an important issue in male infertility. Screening Y chromosome microdeletion is mainly done using polymerase chain reaction (PCR) on blood leukocytes. However, there is some evidence indicating that presence of DAZ in somatic cells might not be indicative of its presence in the germ cell lineage. Therefore, a total of 130 men with poor semen quality were examined for presence of DAZ microdeletion in their leukocytes. From these, sperm from 40 randomly selected men with no DAZ microdeletions in their leukocytes (n?=?10 oligozoospermia; n?=?10 asthenozoospermia; n?=?10 oligoasthenozoospermia; and n?=?10 near-azoospermia) were were compared to sperm from men of normal semen quality (n?=?10) using combined primed in situ labelling and fluorescent in situ hybridization (PRINS-FISH) technique as well as screening for sex chromosome aneuploidy. There was an increased frequency of DAZ microdeletion in blood samples from oligozoospermic (5%) (p?p?DAZ microdeletion was observed in the sperm of patients with no DAZ microdeletion in their leukocytes compared to control (p?DAZ microdeletion induction during spermatogenesis.     

Cytologic investigation of human in vitro fertilization failures

A cytogenetic study of unsuccessfully fertilized oocytes was done for information on the frequency and type of chromosomal abnormalities leading to preimplantation loss. Of 72 oocytes, 44 were assessed as mature, 19 as intermediate, and 9 as immature. The mean fertilization rate was 68%. This rate was significantly lower in immature oocytes than in mature ones (22% versus 79%). Immature oocytes completed maturation in vitro up to metaphase II of meiosis. Intermediate oocytes became fertilizable, however, a significant proportion showed morphologic abnormalities after fertilization. Thus, eggs with three pronuclei were hypotriploid or had three prophasic chromosome sets, together with polyspermy and with first polar body chromosomes. Eggs with developmental arrest showed marked asynchrony in pronuclear morphogenesis. One had a chromosome complement of 24,XX. It is concluded that insemination prior to completion of maturation leads to abnormal development.     

High sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa in obstructive azoospermic men

Purpose: To evaluate the frequencies of sex chromosome aneuploidy and diploidy rate of epididymal spermatozoa from obstructive azoospermic men and its impact on intracytoplasmic sperm injection (ICSI) outcomes. Methods: Epididymal spermatozoa retrieved from 24 obstructive azoospermic men and ejaculated spermatozoa from 24 fertile donors were analyzed using triple color fluorescence in situ hybridization (FISH) techniques, in order to investigate the rates of diploidy and aneuploidy for chromosomes 18, X and Y. Results: Epididymal spermatozoa from obstructive azoospermic men had total sex aneuploidy, disomy 18, and diploidy rates significantly higher than ejaculated spermatozoa from normozoospermic fertile controls (1.44% vs. 0.14%, 0.11% vs. 0.02%, and 0.18% vs. 0.02%, respectively; p < 0.005). There were no statistically significant differences in ICSI outcomes between the patients who had high and low epididymal sperm aneuploidy rate. Conclusions: Epididymal spermatozoa from obstructive azoospermic patients had an elevated sex chromosome aneuploidy and diploidy rate. The increased frequency of chromosomal abnormalities did not have a direct effect on the ICSI outcome.     

Chromosomal constitution of mouse blastocysts derived from oocytes inseminated by multiple sperm insertion into the perivitelline space

Purpose Our purpose was to evaluate the rate of chromosomal aberrations in mouse blastocysts obtained after microinjection of multiple spermatozoa under the zona pellucida of mature oocytes. Without detecting the appearance of pronuclei, the microinjected mouse oocytes containing two polar bodies were cultivated to the blastocyst stage and then analyzed cytogenetically. abResults A chromosome study was carried out in a total of 109 blastocysts derived after microinjection of motile spermatozoa into the perivitelline space. Fifty-five blastocysts (50.5%) exhibited normal diploid chromosome complements, 30 (27.5%) showed different forms of mosaicism, and 24 (22%) exhibited haploidy caused by parthenogenetic activation. Compared to in vivo and in vitro control groups there was a significant increase in the parthenogenesis and mosaic forms of embryos produced by micromanipulation (P <0.001). A total of 360 well-spread metaphases of 103 blastocysts was analyzed to determine whether the micromanipulation procedure increased the chance of aneuploidy. Aneuploid numbers of chromosomes were absent in all the metaphases analyzed. Conclusion Mosaicism and parthenogenesis appear to be increased significantly following microinjection of multiple spermatozoa under the zona pellucida of mouse oocytes, and there was no evidence of aneuploidy.     

Chromosomal abnormalities in patients with oligozoospermia and non-obstructive azoospermia

Purpose

To assess the frequency and types of chromosomal abnormalities in 204 Ukrainian patients with non-obstructive azoospermia and oligozoospermia and 87 men with normozoospermia.

Methods

Cytogenetic studies were performed on peripheral blood lymphocyte samples of 164 men with oligozoospermia, 40 men with non-obstructive azoospermia and 87 men with normozoospermia attending infertility clinic.

Results

Chromosomal abnormalities were detected in 17 % of patients with sperm disorders: in 35 % of men with azoospermia and in 12.7 % of men with oligozoospermia. The frequency of chromosomal abnormalities in patients with sperm disorders was significantly higher, than in patients with normozoospermia (P = 0.0001). An increase in the incidence of chromosomal abnormalities with the decrease of sperm count was observed. Chromosomal abnormalities were detected in 1.1 % of patients with normozoospermia, 6.5 % of patients with mild oligozoospermia (sperm count 5–15 × 10⁶/ml), 18.4 % of patients with severe oligozoospermia (sperm count <5 × 10⁶/ml) and 35 % of patients with azoospermia. A significant increase in the frequency of chromosomal abnormalities in patients with severe oligozoospermia was observed when compared to mild oligozoospermia (P = 0.01). A statistically significant association (P = 0.02) of chromosomal abnormalities and sex chromosome abnormalities (P = 0.0001) with azoospermia when compared to oligozoospermia was observed.

Conclusions

Our results highlight the importance of cytogenetic studies in patients with oligozoospermia (both mild and severe) and non-obstructive azoospermia. The presence of chromosomal abnormalities influences significantly the fertility treatment protocols, as well as provides a definite diagnosis to couples suffering from infertility.     

Aneuploidy involving chromosome 1 in failed-fertilized human oocytes is unrelated to maternal age

Purpose: To study whether maternal meiotic errors in failed-fertilized oocytes involving chromosome 1 occur at frequencies similar to those involving other autosomes, and whether their frequency is affected by maternal age. Methods: Using fluorescence in situ hybridization (FISH), frequencies of aneusomy and chromatid pre-division involving chromosomes 1, 16, 18, and 21 were determined for 273 failed-fertilized oocytes. Results: The aneuploidy rate for chromosome 1 was 15.8%, and was neither age-dependent nor significantly different from that for chromosomes 16, 18 or 21. Only chromosome 16 exhibited an age-dependent increase in aneusomy rates. The frequency of chromatid pre-division was lower for chromosome 1 than for chromosome 18 (11.9% vs. 25.4%; p = 0.01), but not different from that for chromosomes 16 or 21. Conclusion: Aneuploidy involving chromosome 1 in failed-fertilized oocytes is unrelated to maternal age and occurs at a frequency similar to that for chromosomes 16, 18, and 21.     

Chromosome 21 Detection in Human Oocyte Fluorescence In Situ Hybridization: Possible Effect of Maternal Age

Purpose: The purpose of this study was to evaluate, among 100 uncleaved oocytes, the incidence of numerical and structural chromosome 21 and X abnormalities and to analyze the influence of various factors, such as in vitro (IVF) indications, follicle stimulation protocols, and women's age. Methods: We investigated 150 uncleaved oocytes from 128 patients after an IVF attempt. After cytogenetic analysis (Giemsa) 100 oocytes (66%) were selected for fluorescence in situ hybridization (FISH). Fluorescent probes for human chromosomes X and 21 were used simultaneously according to standard procedures for their hybridization and detection. Results and Conclusions: We analyzed by the FISH protocol 100 metaphase II oocytes with 22 to 25 chromosomes. Our results demonstrate a high rate of disomy for chromosome 21 in human oocytes. Among them, eight were disomic (8%) and three were nullosomic (3%) for chromosome 21. Only one disomy of chromosome X was noted. The various indications of IVF and the different folliculogenesis stimulating protocols did not seem to influence the results but suggested a correlation between the maternal age and the aneuploidy rate of chromosome 21.     

Study of the optimum time for human chorionic gonadotropin—Ovum pickup interval in in vitro fertilization

Objective To study the optimum time for ovum pickup after human chorionic gonadotropin (hCG) injection in in vitro fertilization.Design Prospective randomized study.Setting The Egyptian IVF-ET center.Patients Ninety couples with male factor infertility enrolled for intracytoplasmic sperm injection, divided into three groups. Ovum pickup was performed at 35 hr (group A), 36 hr (group B), and 37 hr (group C) after hCG injection.Results Number of metaphase II oocytes was significantly higher in group B compared to group A. There was no significant difference between group B and C. Fertilization rate was equal in all groups. The number of fertilized oocytes was significantly higher in group B as compared to group A, and there was no significant difference between groups B and C.Conclusion Oocyte maturity in gonadotropin releasing hormone analogue agonist/human menopausal gonadotropin stimulated cycles is attained 36 hr after hCG injection. Oocyte retrieval should not be performed before 36 hr, and there is no risk of spontaneous ovulation between 36 and 37 hr.     

Hyaluronidase removal of the cumulus oophorus increases in vitro fertilization

The effect of hyaluronidase removal of the cumulus oophorus on the in vitro fertilization rate of oocytes obtained from patients with poor oocyte fertilizability has been evaluated. Eighty-eight oocytes were obtained from 13 patients undergoing in vitro fertilization and embryo transfer (IVF-ET) for indications of male-factor, immunological, and idiopathic infertility. In addition, patients in whom fertilization did not occur on previous IVF cycles were evaluated in the study. The occytes of each individual patient were randomly assigned into a treatment (removal of the cumulus;N=40 oocytes) or nontreatment group (control;N=48 oocytes). Hyaluronidase was used to remove the cumulus immediately following oocyte retrieval, and insemination was performed 6–8 hr later. The overall oocyte fertilization rate (both treated and untreated) was 42%. The treatment group demonstrated a higher rate of fertilization compared to the nontreatment group (55% vs 31%;P<0.05). Examination of various patient groups revealed a statistically significant difference in fertilization rates between the treated and the untreated oocytes only in the no previous fertilization group (60% vs 28%;P<0.05). A higher rate of fertilization of the treated oocytes was also seen in the immunologic infertility group, however, statistical significance was not achieved (50% vs 25%;P=0.07). Only one clinical pregnancy was achieved in this group of 13 patients. We conclude that in this group of patients, removal of the cumulus prior to insemination may, in some cases, increase the fertilization potential of the oocyte.Presented in part at the 42nd Annual Meeting of the American Fertility Society, September 1986, Toronto, Canada.     

Hormonal stimulation for in vitro fertilization: A comparison of fertilization rates and cytogenetic findings in unfertilized oocytes

Objective The purpose of this study was to compare fertilization and aneuploidy rates after two stimulation protocols in an IVF program.Design This was a retrospective study.Setting The study took place in the IVF laboratory of an Infertility Department.Methods In 349 treatment cycles, clomiphene citrate (CC) and human menopausal gonadotropin (hMG) were used in one group (N =233) and hMG after treatment with a gonadotropin-releasing hormone agonist (GnRHa) in two other groups (long protocol): goserelin (N =73) and buserelin (N =43). Cytogenetic analysis was performed on all unfertilized oocytes in both groups. Results Fertilization rates were significantly higher in the GnRHa/hMG group than in the CC/hMG group, but cleavage rates and embryo quality were not different. Of 736 oocytes prepared for cytogenetic analysis, 256 were karyotyped: 172 were found to be euploid and 84 aneuploid. More oocytes were aneuploid in the GnRHa/hMG group than in the CC/hMG group and this difference was statistically different after analysis of the data using a specially designed mathematical model.Conclusion If no selection against chromosomally abnormal oocytes takes place at the time of fertilization, more abnormal oocytes are harvested with GnRHa/hMG protocols than with CC/hMG. If, on the other hand, there is a selection against oocytes with some chromosomal imbalance, there is no intrinsic effect of GnRH agonists on the chromosomal complement of the oocyte, and the real aneuploidy frequency in all oocytes, fertilized and unfertilized, is the same in the GnRHa/hMG and in the CC/hMG group.     

Incidence of sperm aneuploidy in relation to semen characteristics and assisted reproductive outcome.

OBJECTIVE: To evaluate the incidence of sperm aneuploidy in men screened for infertility and identify any eventual relation with assisted reproductive outcome. DESIGN: Controlled prospective study. SETTING: University hospital-based IVF program. PATIENT(S): Infertile couples who were screened for sperm aneuploidy and evaluated for IVF treatment. INTERVENTION(S): Fluorescence in situ hybridization was used to identify chromosomes 18, 21, X, and Y. The assisted reproductive techniques of IVF and intracytoplasmic sperm injection were used for infertility treatment. MAIN OUTCOME MEASURE(S): The incidence of sperm aneuploidy, semen parameters, fertilization rate, pregnancy characteristics, and rate of neonatal malformations were determined. RESULT(S): Oligozoospermic and teratozoospermic men had a significantly higher incidence of chromosomal abnormalities than men with normal semen parameters (2.7% vs. 1.8%). The increased frequency of sperm aneuploidy did not appear to affect pregnancy losses or the occurrence of neonatal malformations. CONCLUSION(S): Suboptimal semen samples had a higher incidence of aneuploidy. In this study, the increased frequency of chromosomal abnormalities did not have a direct effect on the fertilization rate, pregnancy characteristics, or neonatal outcome.     

Sperm aneuploidy in infertile men

A recent line of research has shown that infertile male patients produce cytogenetically abnormal spermatozoa, despite a normal somatic karyotype, as a result of an altered intra-testicular environment that affects negatively the mechanisms controlling chromosome segregation during cell division. The rate of aneuploid spermatozoa production is significantly higher in patients with abnormal sperm parameters compared with those of normozoospermic subjects or infertile patients with normal sperm parameters. All chromosomes are subject to aneuploidy, although at a different rate; the heterochromosomes are more often altered than are the autosomes. A negative correlation has been reported to exist between aneuploidy and the main sperm parameters, suggesting that greater testicular damage is associated with a greater chance of chromosome malsegregation events. Abnormally-shaped spermatozoa are more likely to have chromosome abnormalities, particularly those with an enlarged head. More studies are necessary, however, to evaluate whether other types of sperm head abnormalities are also associated with an abnormal sperm chromosome complement. The possibility of retrieving testicular or epididymal spermatozoa in patients with azoospermia and using them in assisted reproduction techniques has prompted the evaluation of their chromosomal status. Studies have shown that testicular and epididymal spermatozoa have a greater rate of aneuploidy compared with that of ejaculated spermatozoa. Some authors have also shown that patients with non-obstructive azoospermia have a significantly higher sperm aneuploidy rate compared with that of patients with obstructive azoospermia. Sperm aneuploidy seems to have a negative impact on assisted reproduction technique outcome. Although it does not affect the fertilization rate, an elevated sperm aneuploidy rate is associated with a greater rate of pregnancy failure. Nevertheless, some patients with elevated sperm aneuploidy rate can still achieve a pregnancy, but with an increased risk of generating an aneuploid offspring. Thus, sperm aneuploidy evaluation is recommended in infertile patients with abnormal semen parameters, particularly if they undergo IVF programmes.     

Assessing the Chromosome Copy Number in Metaphase II Oocytes by Sequential Fluorescence in Situ Hybridization

Purpose: Aneuploidy in oocytes is the main cause of failed embryo implantation and of miscarriage. At present, only limited data on the prevalence of aneuploidy in freshly collected human oocytes are available and all studies have been performed with conventional methods for karyotyping. In this feasibility study, multiple-hybridization fluorescence in situ hybridization (FISH) was evaluated as an alternative method to determine the number of chromosomes in oocytes. Methods: Fifty-two spare oocytes were collected from 23 patients treated with gonadotropins for intrauterine insemination or intracytoplasmic sperm injection. A conventional dual color FISH approach using mixtures of chromosome-specific standard alpha-satellite probes was applied consecutively to the chromosomes of the same metaphase II oocyte. Mixtures of three to six probes were designed in order to allow chromosome identification based on signal color and centromeric index. Results: One hybridization cycle was possible in 52 uninseminated metaphase II oocytes, two hybridizations in 43 oocytes (82.7%), three hybridizations in 30 oocytes (57.6%), four hybridizations in 27 oocytes (51.9%), and five hybridizations in 15 oocytes (28.8%). Altogether, 591 chromosomes could be marked (47.4% of the entire chromosome complement, 11.4 chromosomes per oocyte). The most important single factor contributing to technical failure was loss of the oocyte from the slide. Conclusions: This feasibility study demonstrates that multiple-hybridization FISH can be used for the assessment of a larger proportion of the chromosome complement in oocyte as compared to previous studies based on FISH.     

Human sperm chromosome analysis after microinjection into hamster oocytes

Purpose Subzonal sperm insemination (SUZI) into hamster oocytes was performed to establish the karyotypes of the fertilizing spermatozoa.Methods Spermatozoa from two males with normal semen parameters were microinjected. Of 72 (52 + 20) analyzed sperm chromosome metaphases, only 1 (1.4%) was considered abnormal, showing a structural abnormality.Results No hyperhaploidy was observed. Rates of sperm chromosomal abnormalities after microinjection were not higher than those reported previously using zona-free egg insemination, suggesting that the SUZI procedure per se does not increase sperm chromosomal abnormalities.Conclusions The use of subzonal insemination into hamster oocytes for the study of human sperm chromosomes in males with low sperm counts is discussed.     

Evaluation of the developmental competence and chromosomal compliment of mouse oocytes derived from in-vitro growth and maturation of preantral follicles

Purpose To evaluate the developmental potential and aneuploidy rates of in-vitro versus in-vivo grown and matured mouse oocytes. Methods Mice were superovulated to obtain in-vivo matured oocytes. Mouse preantral follicles were also mechanically isolated and cultured in-vitro. In-vitro fertilization (IVF) was performed and fertilization, cleavage, and morula/blastocyst formation rates were compared between groups. Cytogenetic analysis was used to compare oocyte aneuploidy rates and aneuploidy characteristics in the developing embryos. Results In-vivo oocyte maturation resulted in higher IVF fertilization, cleavage, and morula/blastocyst formation rates versus in-vitro follicle culture (96.4% versus 78.5%, p < 0.001; 95.3% versus 77.4%, p < 0.001; 94.1% versus 76.9%, p < 0.001). Total aneuploidy rates were higher in embryos derived from in-vitro matured oocytes versus those grown in-vivo (4.0% versus 1.3%, p < 0.05). Conclusions Results indicate a reduced developmental competency of in-vitro matured oocytes. The data also highlight an increased susceptibility to meiotic errors in early stage follicles undergoing in vitro culture. Capsule Impaired developmental capacity and errors in proper chromosome segregation are observed in mouse oocytes generated from in-vitro preantral follicle culture versus those developed in-vivo.     

Sperm chromosomal abnormalities are linked to sperm morphologic deformities

OBJECTIVE: To describe the association between specific sperm morphologic abnormalities and sperm chromosomal abnormalities on multicolor interphase fluorescence in situ hybridization (FISH). DESIGN: Case report.Reproductive medicine unit in a tertiary referral center. PATIENT(S): Three infertile men with severe oligoasthenospermia and total teratozoospermia who were referred for IVF treatment. MAIN OUTCOME MEASURE(S): Incidence of spermatozoal chromosomal aneuploidy for chromosome 18 and the sex chromosomes by using FISH. RESULT(S): Morphologic assessment of sperm revealed a high incidence of double heads, multinucleated sperm heads, and multiple tails. Hormone profiles and karyotyping of peripheral lymphocytes were normal in the three men. The proportion of sperm with disomy, trisomy and tetrasomy for chromosome 18, and the sex chromosomes in each patient was 100%, 76%, and 82.5%, respectively. CONCLUSION(S): Specific morphologic abnormalities of sperm may be associated with higher incidence of chromosomal abnormalities. Resolving infertility by offering patients in vitro fertilization/intracytoplasmic sperm injection must be approached with caution because of the significant risk for embryonic aneuploidy and chromosomal abnormalities in any subsequent offspring.