Studies on sperm chromosomes in patients with severe male factor infertility undergoing assisted reproductive technology treatment

Basic diagnostics in andrology

Basic andrological diagnosis consists of taking the patient's medical history and the couple's history as well as performing a physical examination including genital ultrasound, spermiogram, and hormonal analysis. If needed, a testicular biopsy and genetic testing may also be performed. Recent studies have shown the effect of lifestyle factors on male fertility. Thus, the patient history and clinical/andrological examinations have been broadened to include information on metabolic disorders like obesity and diabetes mellitus. The biggest changes occurred with the publication of the fifth edition of the WHO laboratory manual in 2010 and the introduction of a section on semen analysis in the German Medical Association guidelines (RiliBÄK). The reference values for almost all spermiogram parameters were adapted in an evidence-based approach using worldwide prospective population studies. For central parameters such as sperm motility and morphology, the assessment criteria were changed. New independent markers such as sperm DNA fragmentation rate are now routinely used in clinical diagnosis. For German andrological laboratories, there are now mandatory quality assurance measures for semen analysis (in the German "Rili-BÄK" guidelines). These include duplicate testing of all standard semen parameters and inter-laboratory comparison at regular intervals.

Testicular sperm retrieval and intra cytoplasmic sperm injection provide favorable outcome in spinal cord injury patients, failing conservative reproductive treatment

STUDY DESIGN

Retrospective cohort analysis.

OBJECTIVES

The objective of this study was to determine the in vitro fertilization (IVF) outcome after testicular sperm extraction (TESE) in a group of spinal cord injury (SCI) male patients not compatible with conservative fertility treatment.

SETTING

University-affiliated medical center.

METHODS

Thirty two SCI patients (C2 to L2) were referred to IVF after repeated trials of electroejaculation (EEJ) or penile vibratory stimulation (PVS), and full andrological evaluation. Testicular sperm aspiration (TESA) was the method of choice for sperm extraction. Open TESE was performed only after a negative TESA attempt. Clinical pregnancy and live birth rates were determined.

RESULTS

A total of 106 testicular procedures were performed. Sperm was found in 95 cycles (89.6%). The average metaphase II (MII) oocyte number was 11.0±4.2, an average of 5.1±2.3 oocytes became normally fertilized after Intra Cytoplasmic Sperm Injection (ICSI) (fertilization rate 57.1%). On average, 2.7±1.2 embryos were replaced. The clinical pregnancy rate was 32/106 (30.2%) per cycle and 19/32 (59.3%) per couple. Live birth rate was 62.5% (20/32).

CONCLUSIONS

TESA/E and IVF can provide excellent prognosis for SCI patients that cannot be treated by EEJ or PVS.

Male fertility and reduction in semen parameters: a single tertiary-care center experience

Background. Infertility is both a clinical and a public problem, affecting the life of the couple, the healthcare services, and social environment. Standard semen analysis is the surrogate measure of male fertility in clinical practice. Objective. To provide information about the relationship between semen parameters and spontaneous conception. Methods. We evaluated retrospectively 453 pregnancies that occurred among 2935 infertile couples evaluated at an infertility clinic of a tertiary-care university hospital, between 2004 and 2009. Results. Normal semen analysis was present only in 158 patients; 295 subfertile patients showed alterations in at least one seminal parameter. A reduction in all seminal parameters was observed in 41 patients. Etiological causes of male infertility were identified in 314 patients. Conclusion. Our data highlights the possibility of a spontaneous conception with semen parameters below WHO reference values. Therefore, we support the importance of defining reference values on a population of fertile men. Finally, we analyzed the related ethical issues.

Sperm aneuploidies after human recombinant follicle stimulating hormone therapy in infertile males

Errors in sperm chromosome segregation are frequently observed in infertile males. It would therefore be useful to develop methods for reducing the rate of aneuploidy in spermatozoa. Thirty-one males were selected with an elevated frequency of total sperm aneuploidy of sperm chromosomes 18, X and Y by fluorescence in-situ hybridization (FISH): 22 were treated with 150 IU of recombinant FSH on alternate days for 3 months and the other nine (controls) did not receive any hormonal treatment. Before therapy, FISH analysis demonstrated an increased frequency of diploidy (0.663 +/- 0.09%), disomy (0.412 +/- 0.03%) and total aneuploidy (1.30 +/- 0.12%) in the 22 males. Sperm analyses revealed reduced progressive motility (26.73 +/- 2.3%) and a reduced percentage of spermatozoa with normal morphology (23.86 +/- 5.3%). After 90 days of therapy, a significant reduction in aneuploidies (mean total aneuploidy: 0.86% +/- 0.11; P = 0.005) was obtained, as well as an improvement in functional and structural sperm characteristics. In untreated patients, no significant change in semen parameters and frequency of total aneuploidy was observed between baseline (1.054 +/- 0.06%) and 90 days later (1.080 +/- 0.05%). It is therefore suggested that deranged meiotic segregation in spermatozoa could be reduced by FSH treatment.

Role of aneuploidy on embryo implantation

Approximately 30% of oocytes in the human species carry a chromosomal imbalance. This condition has severe clinical consequences as approximately one-third of spontaneous abortions are aneuploid. The most obvious link to the increase of aneuploidy in oocytes is maternal age. This has been directly confirmed by the analysis of polar bodies. Their analysis permits to give confirmation of the high predisposition of oocytes to meiotic errors. Also, the study of chromosomes on sperm has revealed a frequency of 6-7% aneuploidy in normal sperm samples, and is significantly increased in cases of severe oligoasthenoteratospermia or azoospermia due to testicular failure. During the preimplantation period there is a progressive loss of abnormal embryos at specific stages in early development, through growth arrest and degeneration of abnormal embryos. The frequency of chromosomal abnormalities is strictly related to the category of patients (advanced maternal age, repeated cycles, altered karyotype, repeated miscarriages, TESE). Based on these considerations, preimplantation genetic diagnosis for aneuploidy is proposed in reproductive medicine with the finality of improving the clinical outcome after IVF. Substantial evidence has been accumulated on the positive impact of the technique, reporting increased implantation rates and a concomitant decrease of spontaneous abortions and trisomic pregnancies.

Single blastocyst transfer after ICSI from ejaculate spermatozoa, percutaneous epididymal sperm aspiration (PESA) or testicular sperm extraction (TESE)

PURPOSE

To investigate the outcome of IVF following intracytoplasmic sperm injection (ICSI) from ejaculate, percutaneous epididymal sperm aspiration (PESA) and testicular sperm extraction (TESE), with subsequent blastocyst culture and single blastocyst transfer.

METHODS

Single blastocyst transfer was performed after ejaculate ICSI (oligozoospermia) in 587 patients, TESE/PESA (azoospermia) in 31 patients, and standard IVF in 680 women.

RESULTS

There were only minor differences in IVF characteristics between the standard IVF and the PESA-TESE couples. Couples where ejaculate ICSI were performed seemed to represent a slightly poorer prognostic group. A viable fetus after the 12th gestational week, i.e. ongoing pregnancy, was present in 41.4% after ICSI/ET, 51.6% after PESA-TESE/ET and in 40.4% after standard IVF/ET (no significant differences).

CONCLUSION

Single blastocyst transfer after ejaculate ICSI or after PESA/TESE appears to give similar results as conventional IVF blastocyst culture.

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.

DESIGN

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.

SETTING AND PATIENT(S)

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

INTERVENTION(S)

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).

MAIN OUTCOME MEASURE(S)

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

RESULT(S)

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%).

CONCLUSION(S)

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.

The role of preimplantation diagnosis for aneuploidies

The clinical application of preimplantation genetic diagnosis (PGD) for aneuploidy has confirmed the hypothesis that implantation failure and spontaneous abortions are frequently due to aneuploidy. Following PGD, a higher implantation rate and a lower incidence of spontaneous abortions are obtained in patient categories where aneuploidy is the main cause of reproductive failure: women in advanced reproductive age, patients with an altered karyotype due to translocations or gonosomal mosaicism, and patients with recurrent spontaneous abortions. In these cases, the transfer of euploid embryos overcomes the poor prognosis condition in these couples. As expected, aneuploidy increases proportionally with female age; however, not all the chromosomes studied show this trend, suggesting that segregation errors could occur at different rates for each chromosome in relation to maternal age. Furthermore, the retrospective analysis of the results obtained in patients who repeated at least twice a PGD cycle permitted to estimate their chances of reproducing the same pattern of chromosomal abnormalities and consequently evaluating their possibility of a pregnancy: when no euploid embryos are detected at the first attempt, the chance of on-term pregnancy is below 10%; however, this chance is approximately 30% for couples with at least two euploid embryos in the first cycle.

Prognostic value of the clinical and laboratory evaluation in patients with nonmosaic Klinefelter syndrome who are receiving assisted reproductive therapy

OBJECTIVE

To characterize clinical and laboratory findings in nonmosaic 47,XXY patients that may help to predict spermatogenetic activity in their testicles.

DESIGN

Prospective study.

SETTING

Assisted reproductive technology program.

PATIENT(S)

Twenty patients with nonmosaic Klinefelter syndrome who underwent testicular sperm retrieval for IVF.

MAIN OUTCOME MEASURE(S)

The correlation between basal FSH, LH and testosterone levels, mean testicular volume, and results of the hCG test and presence or absence of sperm after testicular sperm extraction (TESE).

RESULT(S)

Sperm was found in nine patients (45%). The mean testicular volume was 7.8 +/- 2.5 mL in men with sperm after TESE and 5.6 +/- 1.2 mL in those without sperm after TESE; corresponding testosterone levels were 3.5 +/- 1.2 ng/mL and 1.7 +/- 0.8 ng/mL. Serum levels of FSH and LH did not significantly differ between groups. After the hCG test, the mean serum testosterone level was 16.0 +/- 6.3 ng/mL in men with sperm after TESE and 6.7 +/- 5.6 ng/mL in those without sperm.

CONCLUSION(S)

Testicular volume, testosterone levels, and results of the hCG test are important predictive factors of spermatogenesis in patients with nonmosaic Klinefelter syndrome.