E. Kasterstein

In vitro maturation of human germinal vesicle-stage oocytes: role of epidermal growth factor-like growth factors in the culture medium

BACKGROUND In vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side effects of gonadotrophin stimulation for IVF. The pregnancy rates from oocytes matured in vitro are still lower than those of in vivo stimulation cycles, indicating that optimization of IVM remains a challenge. Recently, it was demonstrated that LH exerts its action on ovulation, at least in part, through stimulation of the production of the epidermal growth factor family members amphiregulin (Areg) and epiregulin (Ereg) in pre-ovulatory follicles, and they, in turn, serve as paracrine mediators of LH. We aimed to investigate the effect of supplementation of the medium with Areg and Ereg on the maturation rate of immature oocytes. METHODS A total of 105 sibling human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation were cultured in a complex defined medium either with or without supplemented recombinant human Areg (75 ng/ml) and Ereg (75 ng/ml) for 24 h. RESULTS Significantly more oocytes reached the metaphase II stage at 24 h in media supplemented with Areg and Ereg (75.5 versus 36.5%, P < 0.001). In vitro matured oocytes retrieved from the two subgroups had no statistically significant difference in fertilization and cleavage rates or morphology scores. Overall, a significantly higher number of Day 2 (52.8 versus 26.9% P < 0.01) and Day 3 (45.2 versus 23%, P < 0.05) embryos originated from GV oocytes cultured in the Areg- and Ereg-enriched medium. CONCLUSIONS Supplementation of the maturation medium with Areg and Ereg improves the maturation of human GV oocytes in vitro.

Very Low Sperm Count Affects the Result of Intracytoplasmic Sperm Injection

AbstractPurpose: The aim was to examine the influence of extremelylow sperm count on intracytoplasmic sperm injection(ICSI) outcome. Methods: Over 1000 consecutive unselected ICSI cycleswere divided into four groups according to spermconcentration of their patients: A, cryptozoospermia, 107 patients; B,sperm concentration of ≤ 1×104, 146 patients; C, spermcount of 1×104–1×105, 135 patients; and concentration of≤ 1×105 and < 10×106/ml (control group), 688 patients. Results: A significant decrease in pregnancy rate wasnoticed in the cryptozoospermic group in comparison to thecontrol group (20% vs. 31%). Fertilization rate in group Awas significantly lower in comparison to all other groups,respectively (46% vs. 52%, 54%, 61%). Embryo quality wasinferior in group A in comparison to the control group. Ahigher yet not statistically significant abortion rate wasobserved in the cryptozoospermic group (as well as in groupC) (30%, 27%) compared to the control group (15%). Conclusions: It seems that an extremely low sperm counthas a negative effect on the outcome of ICSI. Neverthelesspatients with cryptozoospermia should not be offered ICSItreatment with the ejaculated sperm before karyotype isestablished.

Increased frequency of female partner chromosomal abnormalities in patients with high-order implantation failure after in vitro fertilization

OBJECTIVE To find the type and frequency of chromosomal abnormalities in a selected group of high-order implantation failure (> or =6 IVF trials and > or =15 transferred embryos) and to evaluate its impact on pregnancy outcome. DESIGN A retrospective study. SETTING In vitro fertilization (IVF) unit in a university affiliated hospital. PATIENT(S) Sixty-five couples with high-order implantation failure in IVF and embryo transfer. INTERVENTION(S) In vitro fertilization/embryo transfer (ET), work-up for implantation failure, cytogenetic analysis of the couple. MAIN OUTCOME MEASURE(S) We studied the type and frequency of chromosomal changes, quality of embryos, cumulative pregnancy rates, and pregnancy outcome. RESULT(S) The mean number of treatment cycles per patient, before karyotyping was 7.8 +/- 2.4 (range: 6 to 16 cycles). The mean cumulative number of all transferred embryos per patient was 25.7 +/- 10.3 (range: 9 to 65 embryos). Chromosomal abnormalities were found in 10 of 65 (15.4%) cases: translocations in six, mosaicism in two, and inversion or deletion in another two. The morphologic characteristics of the transferred embryos and the cumulative pregnancy rates were similar in patients with implantation failure with and without chromosomal changes. Three of the 16 patients with abnormal karyotype delivered and three miscarried within a follow-up period of 1 year. CONCLUSION(S) A high frequency of chromosomal aberrations was found in a selected group of high-order implantation failures, a similar frequency to recurrent miscarriages. Karyotyping is recommended as part of the work-up for repeated implantation failure in assisted reproduction. Treatment options include further IVF trials, preimplantation genetic diagnosis, or oocyte donation, tailored according to the type of chromosomal change. An international registry should be considered to assist in counseling these patients.

The cytogenetic constitution of embryos derived from immature (metaphase I) oocytes obtained after ovarian hyperstimulation

OBJECTIVE To examine the chromosomal content of embryos resulting from metaphase I (MI) oocytes obtained after ovarian hyperstimulation for IVF. DESIGN Prospective cohort study. SETTING University-based IVF Center, Assaf Harofeh Medical Center, Tel Aviv University, Israel. PATIENT(S) One hundred fifty women undergoing assisted reproduction technique (ART). INTERVENTION(S) Intracytoplasmic sperm injection (ICSI) was performed in MI oocytes that were retrieved after ovarian stimulation. A portion of these oocytes extruded their polar body (rescued in vitro-matured metaphase II [IVM-MII]) after different incubation periods and the remainder did not (arrested MI oocytes). Fluorescence in situ hybridization was performed using probes for chromosomes X, Y, 18. MAIN OUTCOME MEASURE(S) Fertilization rate, number of blastomeres, and embryo euploidy. RESULT(S) Embryos from rescued IVM-MII oocytes showed significantly higher fertilization rates and more blastomeres per embryo compared with those from arrested MI oocytes (58.5% vs. 43.9% and 5.7 vs. 5.0, respectively). The chromosomal analysis of these embryos revealed a high rate of aberrations (80.6%), mainly complex mosaics. This rate was elevated in embryos from arrested IVM oocytes (97.2%), and after longer incubation periods. No chromosomally normal embryos were found after 24 hours of incubation of their corresponding oocytes. CONCLUSION(S) Embryos originating from MI oocytes have a high rate of chromosomal aneuploidy, and their replacement should be reconsidered.

Presence of IL-18 in testicular tissue of fertile and infertile men.

Recently, IL‐18 was identified in human testes. Moreover, an inverse correlation was found between the levels of IL‐18 and the number and motility of spermatozoa. We examined the presence of IL‐18 protein in normal and impaired spermatogenesis. Testicular tissue specimens were taken from 25 nonobstructive azoospermic patients undergoing testicular sperm extraction and from autopsies of three healthy controls. The presence of IL‐18 in human testicular cells was examined by immunohistochemical staining of paraffin‐embedded sections, using a specific antibody for human IL‐18. In testicular tissue of healthy controls as well as in study cases, presence of IL‐18 was identified in somatic, mitotic, meiotic and post‐meiotic cells in correlation with their presence. In all patients, Leydig cells were less intensively stained. Mitotic cells were immunostained in the control group and less intensively in hypospermatogenesis and maturation arrest subgroups. Primary spermatocytes were in general most efficiently stained. The expression of IL‐18 mRNA (as examined by real‐time PCR analysis) showed significantly lower expression in testicular tissues with impaired spermatogenesis when compared to normal tissues. We report the first study demonstrating the presence of IL‐18 in human testicular tissue at the protein level. The presence of this cytokine in somatic as well as in different types of germ cells may suggest its involvement in the regulation of the spermatogenic process and steroidogenesis under physiological and pathological conditions.

Computerized cell-scanning system for evaluating human spermatogenesis in non-obstructive azoospermic patients

There may be incompatibility between testicular histopathological evaluation and testicular sperm extraction (TESE) outcome. Assessment for sperm presence and different pathological disturbances of non-obstructive azoospermia (NOA) remains challenging. An assay for maximal sampling and accurate identification of testicular cells from NOA patients undergoing TESE and autopsied fertile controls was developed. Testicular cells stained and scanned automatically for morphology underwent fluorescence in-situ hybridization using centromeric probes for chromosomes X, Y and 18 after destaining. Cells were automatically classified according to ploidy, and ratios of haploid cells and autosomal (18) and sex-chromosome bivalent rates were calculated. Identification of testicular cells in suspension enabled prediction of spermatogenesis in seven of eight Sertoli-cell-only syndrome patients. Haploid/diploid cell ratios were 67.6:32.2 for controls and 9.6:90.4 for patients. Both autosomal (18) and sex-chromosome bivalents were present in patients (4.1 ± 5.82%) and controls (19.7 ± 8.95%). Few tetraploid pachytene spermatocytes were observed. More secondary spermatocytes with NOA showed two distinct signals for chromosome 18 (27.9 ± 32.69%) compared with controls (0.4 ± 0.35%). The computerized cell-scanning system enables simultaneous application of morphology and chromosome analysis of testicular cells, which enhance assessing different pathological disturbances and estimating the likelihood of a successful second TESE procedure.

Reproductive Performance of Patients Undergoing Intracytoplasmic Sperm Injection with 100% Implantation Rate

Purpose: To characterize the differences between twomatched groups of patients treated by ICSI: those pregnantafter all embryos transferred implanted (100% implantationrate) compared with nonpregnant patients. Methods: Twenty-one patients in whom one transferredembryo achieved a singleton pregnancy (group A) and 21pregnant patients to whom two or three embryos were transferredand achieved 11 twin and 10 triplet pregnancies(group B) compared with matched nonpregnant patients(group C and D, respectively). Results: The singleton pregnant patients were significantlyolder than the twin and triplet pregnancy patients. Althougha similar number of human menopausal gonadotropinampules were used in the singleton compared with the twinsand triplets a significantly lower number of oocytes andembryos were achieved at lower levels of estradiol on thehuman chorionic gonadotropin day in the former than inthe latter respectively. No difference was found between thepregnant women and their nonpregnant controls in any ofthe mentioned parameters. Good embryo morphology wasfound in 86% of the embryos in group A compared with62% in group C (P = 0.08) and 92% in group B comparedwith 66% in group D (P < 0.002). Conclusions: The only parameter in which pregnant patientswith 100% implantation rate differ from their nonpregnantcontrols was embryo quality.

Fertilizing Capability of Frozen-Thawed Immotile Sperm

The introduction of intracytoplasmic sperm injection (ICSI) for severe male cases has made it possible to treat patients with azoospermia, in whom sperm is achieved from the epididymis and the testis (1–3). In some of the treated male patients, especially those with non-obstructive azoospermia, mainly immotile spermatozoa are available. Because it is assumed that the fertilizing potential of testicular sperm is lower (4) and motility is an important predictive factor for successful fertilization (5) it should be questioned whether ICSI perfomed with immotile sperm is justified.