Calvin Greene

A comparison of the frequency of sperm chromosome abnormalities in men with mild, moderate, and severe oligozoospermia

Abstract Infertile men undergoing intracytoplasmic sperm injection have an increased frequency of chromosome abnormalities in their sperm. Men with low sperm concentration (oligozoospermia) have an increased risk of sperm chromosome abnormalities. This study was initiated to determine whether men with severe oligozoospermia (<106 sperm/ml) have a higher frequency of chromosome abnormalities in their sperm compared with men with moderate (1–9 × 106 sperm/ml) or mild (10–19 × 106 sperm/ml) oligozoospermia. Multicolor fluorescence in situ hybridization analysis was performed using DNA probes specific for chromosomes 13, 21, X, and Y (with chromosome 1 as an autosomal control for the sex chromosomes). Aneuploidy and disomy frequencies were assessed from a total of 603 011 sperm from 30 men: 10 in each of the categories. The mean frequencies of disomy for the patients with mild, moderate, and severe oligozoospermia were 0.17%, 0.24%, and 0.30%, respectively, for chromosome 13 and 0.22%, 0.44%, and 0.58%, respectively, for chromosome 21. For the sex chromosomes, the mean frequencies of disomy for mild, moderate, and severe oligozoospermia were 0.25%, 1.04%, and 0.68%, respectively, for XY, 0.047%, 0.08%, and 0.10%, respectively, for XX, and 0.04%, 0.06%, and 0.09%, respectively, for YY. The frequencies for diploidy also increased from 0.4% for mild to 1.20% for moderate to 1.24% for severe oligozoospermia. There was a significant inverse correlation between the frequency of sperm chromosome abnormalities and the sperm concentration for XY, XX, and YY disomy and diploidy. These results demonstrate that men with severe oligozoospermia have an elevated risk for chromosome abnormalities in their sperm, particularly sex chromosome abnormalities.

Immunofluorescent synaptonemal complex analysis in azoospermic men

The molecular cause of germ cell meiotic defects in azoospermic men is rarely known. During meiotic prophase I, a proteinaceous structure called the synaptonemal complex (SC) appears along the pairing axis of homologous chromosomes and meiotic recombination takes place. Newly-developed immunofluorescence techniques for SC proteins (SCP1 and SCP3) and for a DNA mismatch repair protein (MLH1) present in late recombination nodules allow simultaneous analysis of synapsis, and of meiotic recombination, during the first meiotic prophase in spermatocytes. This immunofluorescent SC analysis enables accurate meiotic prophase substaging and the identification of asynaptic pachytene spermatocytes. Spermatogenic defects were examined in azoospermic men using immunofluorescent SC and MLH1 analysis. Five males with obstructive azoospermia, 18 males with nonobstructive azoospermia and 11 control males with normal spermatogenesis were recruited for the study. In males with obstructive azoospermia, the fidelity of chromosome pairing (determined by the percentage of cells with gaps [discontinuities]/splits [unpaired chromosome regions] in the SCs, and nonexchange SCs [bivalents with 0 MLH1 foci]) was similar to those in normal males. The recombination frequencies (determined by the mean number of MLH1 foci per cell at the pachytene stage) were significantly reduced in obstructive azoospermia compared to that in controls. In men with nonobstructive azoospermia, a marked heterogeneity in spermatogenesis was found: 45% had a complete absence of meiotic cells; 5% had germ cells arrested at the zygotene stage of meiotic prophase; the rest had impaired fidelity of chromosome synapsis and significantly reduced recombination in pachytene. In addition, significantly more cells were in the leptotene and zygotene meiotic prophase stages in nonobstructive azoospermic patients, compared to controls. Defects in chromosome pairing and decreased recombination during meiotic prophase may have led to spermatogenesis arrest and contributed in part to this unexplained infertility.

Chromosome Abnormalities in Sperm From Infertile Men with Asthenoteratozoospermia

Abstract Research over the past few years has clearly demonstrated that infertile men have an increased frequency of chromosome abnormalities in their sperm. These studies have been further corroborated by an increased frequency of chromosome abnormalities in newborns and fetuses from pregnancies established by intracytoplasmic sperm injection. Most studies have considered men with any type of infertility. However, it is possible that some types of infertility have an increased risk of sperm chromosome abnormalities, whereas others do not. We studied 10 men with a specific type of infertility, asthenozoospermia (poor motility), by multicolor fluorescence in situ hybridization analysis to determine whether they had an increased frequency of disomy for chromosomes 13, 21, XX, YY, and XY, as well as diploidy. The patients ranged in age from 28 to 42 yr (mean 34.1 yr); they were compared with 18 normal control donors whose ages ranged from 23 to 58 yr (mean 35.6 yr). A total of 201 416 sperm were analyzed in the men with asthenozoospermia, with a minimum of 10 000 sperm analyzed per chromosome probe per donor. There was a significant increase in the frequency of disomy in men with asthenozoospermia compared with controls for chromosomes 13 and XX. Thus, this study indicates that infertile men with poorly motile sperm but normal concentration have a significantly increased frequency of sperm chromosome abnormalities.

Sperm chromosome aneuploidy analysis in a man with globozoospermia

OBJECTIVE To determine the frequencies of chromosome aneuploidy and diploidy in sperm from a male with globozoospermia. DESIGN Assessment of sperm chromosome aneuploidy and diploidy frequencies by multicolor fluorescence in situ hybridization (FISH) analysis. SETTINGS University research laboratory. PATIENT(S) An infertile patient with round-headed sperm (globozoospermia). INTERVENTION(S) Sperm samples were obtained by masturbation for cytogenetic analysis. MAIN OUTCOME MEASURE(S) Aneuploidy and diploidy frequencies were assessed by multicolor FISH analysis for chromosomes 1, 15, 21, X, and Y and compared with those of five control donors. RESULT(S) A minimum of 10,000 sperm was analyzed per chromosome probe, for a total of 30,145 sperm. There was a statistically significantly increased frequency of XY disomy in the man with globozoospermia compared with the case in normal donors. The frequency of aneuploidy for chromosomes 1, 15, 21, XX, and YY was not statistically significantly increased. The frequency of diploidy was also not statistically significantly different. CONCLUSION(S) A previous report demonstrated an increased frequency of chromosome 15 aneuploidy in sperm of a globozoospermia patient who fathered a trisomy 15 conceptus. No other report has studied the frequency of chromosome 15 aneuploidy in these infertile men. Our study does not demonstrate an increased risk for chromosome 15 aneuploidy associated with globozoospermia. However, an elevated frequency of XY disomy was discovered, which is the most common type of chromosome abnormality observed in sperm of infertile men.

A prospective randomized trial of conventional in vitro fertilization versus intracytoplasmic sperm injection in unexplained infertility

Purpose: To compare outcomes in patients with unexplained infertility undergoing conventional in vitro fertilization (IVF) versus intracytoplasmic sperm injection (ICSI). Methods: Sixty women with unexplained infertility in a Canadian tertiary-level clinic were randomized to IVF or ICSI. Subjects underwent downregulation with gonadotropin-releasing hormone agonist prior to initiation of recombinant human follicle-stimulating hormone. The primary outcome measure was fertilization rate. Secondary outcomes included implantation rate, embryo quality, clinical pregnancy rate, and live birth rate. Results: There was no statistically significant difference in fertilization rate (77.2% IVF vs. 82.4% ICSI), implantation rate (38.2% IVF vs. 44.4% ICSI), clinical pregnancy rate (50% in each group), or live birth rate (46.7% IVF vs. 50% ICSI). There were two cases of failed fertilization in the IVF group. There was no significant difference in embryo quality between groups. Conclusions: There were no differences in clinical outcomes associated with IVF versus ICSI in the treatment of unexplained infertility.

Incidence and complications of multiple gestation in Canada: proceedings of an expert meeting

This paper reports the proceedings of a consensus meeting on the incidence and complications of multiple gestation in Canada. In addition to background presentations about current and possible future practice in Canada, the expert panel also developed a set of consensus points. The need for infertility to be understood, and funded, as a healthcare problem was emphasized, along with recognition of the emotional impact of infertility. It was agreed that the goal of assisted reproduction treatment is the delivery of a single healthy infant and that even though many positive outcomes have resulted from twin or even triplet pregnancies, the potential risks associated with multiple pregnancy require that every effort be made to achieve this goal. The evidence shows that treatments other than IVF (such as superovulation and clomiphene citrate) contribute significantly to the incidence of multiple pregnancy. There is an urgent need for studies to understand better the usage and application of these other fertility technologies within Canada, as well as the non-financial barriers to treatment. The final consensus of the expert panel was that with adequate funding and good access to treatment, it will be possible to achieve the goal of reducing IVF-related multiple pregnancy rates in Canada by 50%.

Exogenous control of the cycle simplifies thawed embryo transfer and results in a pregnancy rate similar to that for natural cycles

To determine if a satisfactory PR could be achieved in thawed ET using a simplified protocol, standard monitoring in the natural cycle was compared with a controlled preparation of the endometrium with exogenous E2 and P without hormonal or ultrasonographic monitoring. All patients had normal ovarian function, and no GnRH-a were administered. Pregnancy rates, ongoing PRs, and embryo implantation rates were similar in the two groups. The use of exogenous E2 and P without GnRH-a suppression to control the cycle for thaw ET is safe, convenient, and results in PRs at least as good as in the natural cycle. It may be of particular value in patients with an irregular cycle or in those for whom prolonged monitoring is undesirable.

Analysis of chromosome segregation in sperm from a chromosome 2 inversion heterozygote and assessment of an interchromosomal effect

Using fluorescence in situ hybridization (FISH) analysis, the chromosome segregation of a pericentric inversion of chromosome 2 was studied in spermatozoa. An interchromosomal effect (ICE) was also determined for chromosomes 13, 21, X, and Y. This chromosome inversion included more than 2/3 of the total length of the chromosome and the breaks points were in G‐light bands. The frequency of non‐recombinant sperm was 55.9%, and that of recombinant sperm was 34.5% (with a 1:1 ratio of duplication of the p arm and deletion of the q arm and vice versa). There was a significantly increased frequency of disomy for chromosome 2 (0.6%) compared to the other autosomes, suggesting that pairing and recombination of the inversion may predispose to nondisjunction. There was no significant difference between the frequencies of aneuploidy for chromosomes 13, 21, X, and Y for the chromosome inversion heterozygote compared to control donors. Thus we did not find evidence for an ICE.

Improved pregnancy rates with luteinizing hormone supplementation in patients undergoing ovarian stimulation for IVF

IntroductionLuteinizing hormone (LH) is believed to play a role in follicle maturation during the natural cycle. However, the need for co-treatment with recombinant LH (rLH) for controlled ovarian stimulation is controversial.PurposeThe primary objective of our study was to determine if pregnancy rates are improved when rLH is used in addition to rFSH for ovarian stimulation. Secondary outcomes were fertilization rate, implantation rate and live birth rate.MethodsA retrospective cohort study was performed of 1565 IVF or ICSI cycles. Outcomes were compared between ovarian stimulation cycles from 2007 when rLH and rFSH was used (n = 765) to 2006 when rFSH only was used (n-800).ResultsImproved outcomes were found for rLH + rFSH versus rFSH alone for; pregnancy rate (61% and 54% respectively, p = 0.006), live birth rate (49% and 42% respectively, P = 0.01), fertilization rate (74% versus 72% respectively, p = 0.04 and implantation rate (41% versus 37% respectively, p = 0.03).ConclusionsOur large retrospective cohort study showed an improved pregnancy rate and live birth rate with rLH supplementation. This was associated with an improved fertilization and implantation rate and therefore may reflect an improvement in oocyte quality and/or uterine receptivity.

Failed reversal of sterilization: Transcervical transostial recannulation of occluded fallopian tube

A patient with bilateral occlusion at the site of tubal reanastomosis demonstrated the potential benefits and hazards of attempted transcervical transostial tubal cannulation to restore patency. On one side tubal patency was restored, whereas on the other a false passage was created distal to the reanastomosis.