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Biomedical subjects

J Levron

Publications and source records attributed to J Levron.

At least 19 recordsLinked to original sources

Outcome of pregnancies complicated by severe ovarian hyperstimulation syndrome (OHSS): a follow-up beyond the second trimester.

UNLABELLED: The main aim of this study was to assess the obstetric complications for those pregnancies that are complicated by ovarian hyperstimulation syndrome (OHSS) and continue beyond the first trimester. We checked also for other related serious events that occurred during the first trimester. METHODS: We included only patients whose pregnancies continued beyond the first trimester and compared them with IVF-treated patients displaying moderate ovarian response. RESULTS: We studied 165 patients with OHSS (101 singletons and 64 twins) and 156 IVF control patients (85 singletons and 71 twins). Two serious complications, gestational diabetes mellitus (GDM) and pregnancy-induced hypertension (PIH), were noted in both groups. However, the incidence of these two complications did not differ significantly between the groups. In the OHSS group, GDM presented with an incidence of 9.9% for singletons and 9.4% for twins, and 12.9% and 7.0%, respectively, for the control group. PIH presented as 6.9% for singletons and 10.9% for twins in the OHSS group, and 8.2% and 7.0%, respectively, for the control groups. During the first trimester laparoscopies for suspected ovarian torsion were performed in 13 patients, and in 10 patients the diagnosis were confirmed. CONCLUSIONS: Although patients with OHSS-complicated pregnancies previously reported a relatively high risk of GDM and PIH, the occurrence rates do not differ from a matched control group of normally responding patients who conceived after IVF.

Adult↗

The effect of prolonged cryopreservation on embryo survival.

The purpose of this study was to assess the effects of long-term cryopreservation on the survival and implantation rates of embryos. We performed a matched case-control study comparing 101 women whose embryos were transferred after cryopreservation for 2-9 years, with 101 control women whose embryos were transferred after 6 months or less of cryopreservation. A multiple step-wise logistic regression was performed to determine the independent effect of the duration of cryopreservation, patient age and embryo quality on pregnancy and live birth rates. In the study group, 673 embryos were frozen for 24-108 months and of these 451 were thawed. In the control group, 513 embryos were cryopreserved for up to 6 months and 456 were thawed. The implantation rate was similar (4.5% vs. 5.5%) in both groups. We concluded that the duration of cryopreservation did not adversely affect embryo survival, and prolonged cryopreservation appeared to be a safe treatment option.

Adult↗

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

The aim of the study was to determine the rate of chromosome abnormalities in testicular sperm after intracytoplasmic sperm injection due to severe male factor infertility. The study groups included patient with non-obstructive azoospermia (n=9), obstructive azoospermia (n=10), Klinefelter's syndrome (n=5) and normal controls (n=6, groups I-VI, respectively). The mean serum levels of FSH 17.5+/-8.2 (P<0.05), 3.5+/-2.6, 29.8+/-13.0 (P<0.05) and 3.1+/-0.4 mIU/ml, respectively. The rates of chromosome abnormalities were 19.6% (P<0.001), 8.2% (P<0.001), 6.3 and 1.6%, respectively. Chromosomes X and Y were significantly more involved in the aneuploidy than chromosome 18 in groups I and II. The present findings demonstrate a linkage between gonadal failure (high serum FSH levels) and sperm chromosome abnormalities. Our findings may explain the increased incidence of perinatal sex chromosome abnormalities found in severe male factor patients. Patients with non-mosaic Klinefelter's syndrome have comparable risk for sex chromosomes aneuploidy as the rest of the patients with azoospermia. Therefore, genetic screening during pregnancy or before embryo replacement should be carefully considered in severe male factor patient following in vitro fertilization (IVF).

Aneuploidy↗

Sperm chromosome abnormalities in men with severe male factor infertility who are undergoing in vitro fertilization with intracytoplasmic sperm injection.

OBJECTIVE: To investigate the potential paternal contribution to the risk of fetal chromosomal anomalies after intracytoplasmic sperm injection (ICSI). DESIGN: Spermatozoa isolated from testicular tissue and ejaculated specimens of consenting patients undergoing testicular biopsy and ICSI were analyzed for chromosomes X, Y, and 18 by FISH. SETTING: Assisted reproductive technology program. PATIENT(S): Consenting patients undergoing testicular biopsy and ICSI, severe oligozoospermic patients, and normal fertile donors. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The rate of chromosome abnormalities in testicular sperm with regard to the type of azoospermia and ejaculated sperm compared to healthy men. RESULT(S): The mean serum levels of FSH in the groups with nonobstructive azoospermia (n = 9), obstructive azoospermia (n = 10), severe oligozoospermia (n = 9), and the normal donors (n = 6) were 17.5 +/- 8.2 (P<.05), 3.5 +/- 2.6, 14.6 +/- 3.5 (P<.05), and 3.1 +/- 0.4 IU/mL, respectively. The corresponding rates of sperm chromosome abnormalities among these groups were 19.6% (P<.001), 8.2% (P<.001), 13.0% (P<.001), and 1.6%, respectively. The corresponding rates of disomy among these groups were 7.8% (12 of 153 spermatozoa), 4.9% (18 of 367), 6.2% (109 of 1,751), and 1% (5 of 500 spermatozoa), respectively. Errors in chromosomes X and Y were significantly more common than in chromosome 18. CONCLUSION(S): The present findings demonstrate a linkage between gonadal failure (high serum FSH levels) and the occurrence of sperm chromosome aneuploidies. Our findings may explain the increased incidence of sex chromosome abnormalities found after IVF in the severe male factor patient population. Genetic screening during pregnancy or before embryo replacement should be considered carefully.

Aneuploidy↗

In vitro fertilization following natural cycles in poor responders.

This prospective study was designed to examine the feasibility of natural cycle in vitro fertilization (IVF) in poor responders, and the clinical factors that may predict successful outcome. Twenty-two poor responders underwent IVF treatment with 44 unstimulated cycles. The results of the natural cycles were compared with those of the 55 low-response stimulated cycles of these patients during the 12 months prior to the study. Eighteen (82%) patients had at least one oocyte retrieved, while nine (41%) had at least one cycle with embryo transfer. Two (9%) patients each gave birth to a healthy term baby. These results are comparable with those of the stimulated cycles. Serum early follicular follicle stimulating hormone (FSH) level was found to be the only reliable predictor of oocyte recovery and overall outcome in each specific natural cycle. However, because of great variability in basal FSH levels among different cycles of the same patient, this is not a reliable predictor of outcome in future cycles. We conclude that poor responders are a unique group of patients who may benefit from natural-cycle IVF treatment.

Adult↗

Sperm chromosome analysis and outcome of IVF in patients with non-mosaic Klinefelter's syndrome.

OBJECTIVE: The aim of the study was to determine the potential risk for fetal chromosomal anomalies in non-mosaic Klinefelter's syndrome patients undergoing IVF and intracytoplasmic sperm injection. DESIGN: Individually collected spermatozoa were isolated from wet testicular tissue preparations and fixed on glass slides using micromanipulation. Their nuclei were analyzed for chromosomes X, Y, and 18 by fluorescent in situ hybridization. SETTING: Assisted reproductive technology program. PATIENT(S): Consenting patients with non-mosaic Klinefelter's syndrome undergoing testicular biopsy and IVF (fresh specimens) or following such treatment (cryopreserved specimens). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The rates of numerical chromosome abnormalities for chromosomes X, Y, and 18 among spare testicular sperm and the pregnancy outcome following treatment. RESULT(S): Testicular sperm were found in 8 of 20 patients. Four couples became pregnant following embryo replacement. Sperm chromosomes were analyzed in five patients. One hundred and five sperm of 112 analyzed (93.7%) were normal with X to Y ratio of 50:55 (NS) respectively. Among the 112 sperm tested, seven (6.3%) demonstrated chromosomal abnormalities, of which five were related to the sex chromosomes and two to chromosome 18. One set of triplets, one set of twins, and two singletons (four males and three females) with normal karyotypes were born. CONCLUSION(S): Most of the testicular sperm retrieved from Klinefelter's syndrome patients demonstrates a normal pattern of sex chromosome segregation. Therefore, the risk of transmitting numerical sex chromosome abnormalities is relatively low and probably comparable with the rates found in other severe male factor infertility patient groups.

Chromosome Aberrations↗

Testicular sperm aspiration and intracytoplasmic sperm injection for persistent infection of the ejaculate.

OBJECTIVE: To report the successful use of testicular sperm aspiration and intracytoplasmic sperm injection in the presence of an Escherichia coli-infected ejaculate that previously caused repeated embryo degeneration. DESIGN: Case report. SETTING: University medical center. PATIENT(S): A 38-year-old woman who did not conceive for 6 years with repeated IVF attempts. Escherichia coli was isolated from both the oocyte culture dish and her male partner's ejaculate. INTERVENTION(S): Testicular sperm aspiration and intracytoplasmic sperm injection followed by ET. MAIN OUTCOME MEASURE(S): Clinical outcome. RESULT(S): Establishment of a pregnancy delivered at term. CONCLUSION(S): Patients undergoing IVF treatment who have repeated embryo degeneration caused by bacterial infection originating in the ejaculate may be treated successfully with testicular sperm aspiration and intracytoplasmic sperm injection.

Adult↗

Incidence and perinatal outcome of multiple pregnancies after intracytoplasmic sperm injection compared to standard in vitro fertilization.

PURPOSE: Our purpose was to assess the incidence of multiple pregnancies and their obstetric outcome after intracytoplasmic sperm injection. METHODS: The study group comprised women who delivered twins or triplets after intracytoplasmic sperm injection and standard in vitro fertilization. The incidence and main perinatal outcome of 140 multiple pregnancies resulting from intracytoplasmic sperm injection or standard in vitro fertilization treatment were analyzed. RESULTS: A total of 60 multiple pregnancies was obtained after intracytoplasmic sperm injection (3.4 +/- 1.1 embryos/cycle) and 80 after standard in vitro fertilization (3.3 +/- 2.0 embryos/cycle). The incidence of multiple pregnancy, i.e., 22.6 compared to 20.7%, respectively, was calculated. The obstetric outcome of 47 multiple pregnancies after intracytoplasmic sperm injection was 39 twin deliveries at between 27 and 37 weeks of gestation (mean, 36 +/- 3.3) and 8 successful triplet deliveries between 26 and 36 weeks of gestation (mean 32.6 +/- 2.4). The outcome after regular in vitro fertilization was similar. No major malformations were observed. CONCLUSIONS: The results of this study showed that the incidence of multiple pregnancies after intracytoplasmic sperm injection was similar to that after standard, conventional in vitro fertilization. The perinatal outcome did not differ between both groups.

Adult↗

Rapid visualization of metaphase chromosomes in single human blastomeres after fusion with in-vitro matured bovine eggs.

The present study was aimed to facilitate karyotyping of human blastomeres using the metaphase-inducing factors present in unfertilized eggs. A rapid technique for karyotyping would have wide application in the field of preimplantation genetic diagnosis. When cryopreserved in-vitro matured bovine oocytes were fused with human blastomeres, the transferred human nuclei were forced into metaphase within a few hours. Eighty-seven human blastomeres from abnormal or arrested embryos were fused with bovine oocytes in a preclinical study. Fusion efficiency was 100%. In 21 of the hybrid cells, no trace of human chromatin was found. Of the remaining 66, 64 (97%) yielded chromosomes suitable for analysis. The method was used to karyotype embryos from two patients with maternal translocations. One embryo which was judged to be karyotypically normal was replaced in the first patient, resulting in one pregnancy with a normal fetus. None of the second patient's embryos was diagnosed as normal, and hence none was transferred. The results of the present study demonstrated that the ooplasmic factors which induce and maintain metaphase in bovine oocytes can force transferred human blastomere nuclei into premature metaphase, providing the basis for a rapid method of karyotyping blastomeres from preimplantation embryos and, by implication, cells from other sources.

Adult↗

In-vitro fertilization treatment for severe male factor: the fertilization potential of immotile spermatozoa obtained by testicular extraction.

A retrospective analysis in 50 couples of 53 cycles of intracytoplasmic sperm injection (ICSI) with immotile spermatozoa from testicular-retrieved spermatozoa was performed to evaluate whether total immotile spermatozoa achieved after testicular sperm extraction could fertilize ova and result in pregnancies. We assessed the efficacy of ICSI with totally immotile testicular spermatozoa extracted from the testes of azoospermic patients with severe spermatogenic failure (group 1) and compared these results with those from spermatozoa which were recovered after several hours of incubation and were motile (group 2) at the time of injection. In 19 cycles, only totally immotile spermatozoa were injected at the time of ICSI. For the remaining 34 cycles, at least one motile spermatozoon was found for injection. The oocyte fertilization rates were 51% for group 1 and 62% for group 2 (P < 0.02). Eighteen of 19 cycles in group 1 (90%) and all 34 (100%) cycles in group 2 had embryos for replacement. The mean number of embryos per cycle was 5.2 +/- 0.8 and 7.5 +/- 0.9 in groups 1 and 2 respectively; this and the embryo quality (cumulative embryo scoring = 40 +/- 8 for group 1 and 50 +/- 7 for group 2), and clinical pregnancy rates (15.8% per oocyte retrieval in group 1 and 23.5% in group 2) were not significantly different between groups. Fertilization, cleavage and pregnancy can be achieved with intracytoplasmic testicular sperm injection from patients with immotile spermatozoa, at levels comparable with those of ICSI using motile spermatozoa.

Adult↗

Zygote intrafallopian transfer may improve pregnancy rate in patients with repeated failure of implantation.

OBJECTIVE: To evaluate the efficacy of zygote intrafallopian transfer (ZIFT) on implantation rates and pregnancy rates (PRs) in patients with repeated failure of implantation in IVF-ET cycles. DESIGN: A case-control study. PATIENT(S): Criteria for patient selection included male factor or unexplained infertility, normal uterine cavity, and at least three failures of implantation in IVF-ET cycles in which at least three embryos were placed per transfer. Data on 70 patients who underwent 92 ZIFT cycles are presented. A control group consisted of patients with the same selection criteria who underwent an additional standard IVF-ET cycle during the same time period. INTERVENTION(S): Ovulation induction consisted of down-regulation with GnRH analogue followed by ovarian stimulation with FSH and hMG. Intracytoplasmic sperm injection was performed on the oocytes of all patients with male factor infertility. Zygotes were transferred by laparoscopy into the fallopian tube 24-26 hours after oocyte retrieval. MAIN OUTCOME MEASURE(S): Implantation rates and PRs in the ZIFT and control groups were compared. RESULT(S): The PRs and implantation rates were significantly higher in the ZIFT group than in the control group: 34.2% (24/70) and 8.7% (29/333) versus 17.1% (12/70) and 4.4% (13/289), respectively (P = 0.002 and P = 0.04). The cumulative conception rate for two ZIFT cycles was 59.3%. CONCLUSION(S): Zygote intrafallopian transfer should be considered a beneficial mode of treatment for patients with repeated failure of implantation in IVF and transcervical ET. More prospective randomized studies are needed to support this observation.

Adult↗

Outcome of in vitro fertilization and intracytoplasmic injection of epididymal and testicular sperm extracted from patients with obstructive and nonobstructive azoospermia.

OBJECTIVE: To evaluate IVF outcome after epididymal and testicular sperm retrieval in patients with obstructive or nonobstructive azoospermia. DESIGN: Retrospective clinical analysis. SETTING: Public university-affiliated IVF unit. PATIENT(S): One hundred twenty-three azoospermic patients (178 cycles). INTERVENTION(S): Sixty-three patients (103 cycles) with obstructive azoospermia (group 1) underwent either epididymal or testicular sperm retrieval, and 60 patients (75 cycles) with nonobstructive azoospermia (group 2) underwent testicular sperm retrieval combined with IVF treatment. Mature oocytes were fertilized using intracytoplasmic sperm injection. After sperm preparation, supernumerary spermatozoa were cryopreserved. MAIN OUTCOME MEASURE(S): Oocyte fertilization rate and clinical pregnancy rate (PR). RESULT(S): The oocyte fertilization rate was 48.4% (534/1,104) in group 1 and 41.5% (312/751) in group 2 (not significant [NS] difference). A total of 100 cycles (97.1%) and 62 cycles (82.7%) in the obstructive and nonobstructive groups, respectively, had embryos for replacement (NS difference). The clinical PRs per ET cycle were 24% (24/100) and 17.7% (11/62) in the two groups, respectively. Oocyte fertilization rates, when fresh (46.4%) or frozen-thawed (41.8%) spermatozoa were used, were not significantly different in the two groups. The PR when fresh sperm were used was 23.6% (30/127), versus 14.3% (5/35) when frozen sperm were used (NS difference). The PR for women aged < or = 35 years was similar to that for women >35 years of age (20.7% or 29/140 and 18.2% or 4/25, respectively). CONCLUSION(S): Epididymal and testicular sperm obtained in azoospermic patients can fertilize oocytes successfully and may lead to high fertilization rates and PRs. Freezing of these spermatozoa does not reduce the outcome of treatment significantly.

Adult↗

In vitro fertilization treatment for severe male factor: a comparative study of intracytoplasmic sperm injection with testicular sperm extraction and with spermatozoa from ejaculate.

PURPOSE: Our purpose was to evaluate whether the source of spermatozoa influences the results of intracytoplasmic sperm injection (ICSI) treatment in couples with severe male-factor infertility. METHODS: A retrospective analysis of 40 cases of ICSI with testicular-retrieved spermatozoa, matched with 40 cases of ICSI with ejaculated spermatozoa, was performed. We included only couples with normoovulatory females younger than 37 years who were matched according to the day of ovum pickup with the patients in the study group. RESULTS: Eighty cycles were analyzed: 40 cycles using testicular spermatozoa and 40 cycles using ejaculated spermatozoa. In 32 (80%) of the 40 ICSI transcutaneous needle aspiration cycles, we obtained enough spermatozoa to inject all the mature oocytes retrieved. In eight (20%) cases there were not enough spermatozoa to inject all the oocytes. Only 76 (54%) of 141 available oocytes were injected in these eight patients. The oocyte fertilization rates were 42% for the study group and 55.5% for the controls (P < 0.005). Thirty-six (90%) patients in the group with nonobstructive a zoospermia (NOA) and 37 (92.5%) patients in the oligoteratoasthenospermia (OTA) group had embryos for replacement. The mean cleavage rates per cycle (96% with testicular and 93% with ejaculated spermatozoa), the mean number of embryos per transfer (3.72 +/- 1.6 in the NOA group and 4.24 +/- 1.5 in the OTA group), the embryo quality (cumulative embryo scoring = 34.03 +/- 22.62 in the testicular sperm group and 36.08 +/- 19.28 in the ejaculated sperm group), and the clinical pregnancy rates (22.5% in the NOA patients and 20% in the ejaculate group) were not significantly different between groups. CONCLUSIONS: High fertilization, cleavage, and pregnancy rates can be achieved with intracytoplasmic testicular sperm injection from patients with NOA, reaching levels comparable with those of ICSI using ejaculated spermatozoa.

Adult↗

Cortisol concentrations in follicular fluid of 'low responder' patients.

The study was undertaken to examine any differences existing in total cortisol concentrations in the follicular fluid (FF) of pre-ruptured follicles between 'low responder' patients (group 1, n = 20) and 'good responder' patients (group 2, n = 15). The groups were defined according to how many oocytes had been retrieved during the previous in-vitro fertilization procedure (group 1: three or fewer; group 2: more than three) and total oestradiol concentration at previous in-vitro fertilization (IVF) (group 1: < or = 500 pg/ml; group 2: > 500 pg/ml). All patients were aged 36-43 years (group 1 mean +/- SD: 38.2 +/- 4.7; group 2: 32.1 +/- 3.8 years) and were diagnosed with tubal or unexplained infertility. The total FF cortisol concentrations obtained in conjunction with an IVF procedure were assayed and related to oocyte fertilization. Follicular fluid was analysed for total cortisol content. Only follicles between 19 and 20 mm diameter were analysed in both groups. After aspiration of blood-free FF, total cortisol concentrations were measured by radioimmunoassay, designed for the quantitative measurement of cortisol, and related to oocyte fertilization. Total cortisol concentration in FF from fertilized oocytes was 9.7 +/- 0.6 microg/ml (mean +/- SD) in group 1 compared to 9.2 +/- 4.4 microg/ml in group 2 (not statistically significant). Total cortisol concentrations were not associated with oocyte fertilization and no difference between the groups was found in total cortisol concentrations in the FF of unfertilized oocytes or empty follicles.

Adult↗

Difficult or repeated sequential embryo transfers do not adversely affect in-vitro fertilization pregnancy rates or outcome.

In order to assist the medical team in the decision-making process and in adequate counselling of patients when encountering technical difficulties at the time of embryo transfer, we investigated the effect of difficult embryo transfer, with or without the need for cervical dilatation or repeated sequential attempts because of retained embryos in the catheter system, on in-vitro fertilization (IVF) pregnancy rates and outcome. A total of 854 consecutive embryo transfer procedures were prospectively categorized as (i) easy (smooth, unforced), (ii) difficult (requiring uterine manipulation or increased force or cervical grasping and/or accompanied by trauma), (iii) requiring cervical dilatation, or (iv) multiple (two or three) sequential attempts because of embryos retained in the catheter system. Embryo transfer was easy in 734 cases (85.9%). It was difficult in 72 (8.4%), cervical dilatation was required in 21 (2.5%), and one or two repeated attempts were needed in 27 cases (3.2%). Pregnancy rates for the different categories of embryo transfer were 23.3, 23.6, 23.8 and 29.6% respectively. There were no significant differences in the percentage of the ongoing/delivered pregnancies for the different categories of embryo transfer (69, 64.6, 60 and 62.5% respectively). There were no significant differences in the distribution of embryo transfer types among the six infertility specialists who performed the procedures. To conclude, embryo transfers that are difficult to perform or that require cervical dilatation or repeated attempts do not adversely affect pregnancy rates and outcome following IVF. Cervical dilatation, if needed for patients with cervical stenosis, should be performed at the time of the embryo transfer and not earlier. Surgical transmyometrial embryo transfer or rescheduling patients for delayed embryo transfer could be avoided in most patients. This information is important for patient management and counselling in cases of embryo transfer that are not easy to perform.

Decision Making↗

Cryopreservation of activated mouse oocytes and zygote reconstitution after thaw.

A new approach to cryopreservation of unfertilized oocytes is proposed using techniques of artificial egg activation combined with nuclear transplantation. Matured mouse oocytes were released from metaphase II arrest by brief exposure to alcohol, allowed to progress to the pronuclear stage and then frozen according to a standard freezing protocol in propandiol. After thaw the female pronuclei were enucleated and fused with a male karyoplasts that were divided from in-vivo fertilized zygotes. Reconstituted zygotes, fresh and cryopreserved culture control zygotes were cultured to the blastocyst stage and transferred to pseudopregnant recipients. The rate of blastocyst formation was 75.8, 91.6 and 44.1% respectively. A total of 110, 215 and 70 blastocysts were transferred to pseudopregnant females respectively. The implantation rates were 36.4, 72.0 and 75.7% while the rates of fetal viability at mid-gestation were 15.5 (P < 0.0001), 51.1 and 37.1% respectively.

Animals↗

Concurrent use of flow cytometry and fluorescence in-situ hybridization techniques for detecting faulty meiosis in a human sperm sample.

Routine semen analysis in an infertile patient revealed severe teratospermia associated with malformation of head and tail in 100% of the sperm cells. Flow cytometry and fluorescence in-situ hybridization (FISH) were shown to supplement routine semen analysis by providing information on the sperm chromatin. Using flow cytometry, propidium iodide-stained spermatozoa from the same sperm sample were compared with a normal reference pool, and with human lymphocytes. The results point to a population of diploid sperm cells rather than to mature haploid spermatozoa. Numerical chromosomal abnormalities of the spermatozoa were subsequently evaluated using FISH. A total of 1000 sperm cells were scored for X and Y chromosomes, and an additional 1128 sperm cells for chromosome 18. Aneuploidy of chromosomes X and Y was revealed in 96.9% of the cells and of chromosome 18 in 90.3% of the cells. Non-disjunction of chromosome X and Y in meiosis I and II occurred in 54.8 and 2.7% of the sperm cells respectively. Non-disjunction in both meiosis I and II occurred in 39.4% of the sperm cells. A normal haploid pattern for chromosomes X and Y was observed in only 3.1%, and for chromosome 18 in 9.7%, of the cells. Using three colour FISH for the sex chromosomes and for chromosome 18, diploidy was demonstrated in 19.4% of 500 sperm cells and aneuploidy in virtually all sperm cells (99.2%). The use of flow cytometry and FISH in cases where genetic and developmental chromatin abnormalities are suspected is a valuable adjunct to other available techniques, and can guide the clinicians to decide which samples are unsuitable for intracytoplasmic injection.

Adult↗

Ooplasmic transfer in mature human oocytes.

Ooplasmic transplantation aimed at restoring normal growth in developmentally compromised oocytes and embryos was evaluated in seven couples (eight cycles) with multiple implantation failures. Two approaches were investigated to transfer ooplasm from donor eggs at metaphase II (MII) stage into patient MII eggs: (i) electrofusion of a ooplasmic donor fragment into each patient egg (three cycles), and (ii) direct injection of a small amount of ooplasm from a donor egg into each patient egg (five cycles). Some donor eggs were used multiple times. Donor eggs were divided into two groups, one being used for ooplasmic extraction and the other one for egg donation. Cleaved embryos resulting from the latter were cryopreserved, where numbers and satisfactory development permitted. A second control group consisted of embryos derived from patient eggs after intracytoplasmic sperm injection without ooplasmic transfer. This was performed when sufficient number of eggs were available (n = 5). Donor eggs (n = 40) were evaluated cytogenetically after micromanipulation in order to confirm the presence of chromosomes. One egg was anuclear and the recipient embryos were not transferred. Normal fertilization was significantly higher after injection of ooplasm (63%) in comparison with fusion (23%). Pronuclear anomalies appeared enhanced after fusion with ooplasts. Embryo morphology was not improved in the three cycles with electrofusion and patients did not become pregnant. An improvement in embryo morphology was noted in two patients after injection of ooplasm and both became pregnant, but one miscarried. A third pregnancy was established in the repeat patient, without obvious embryo improvement. One baby was born and the third pregnancy is ongoing with a normal karyotype. Two other patients with male factor infertility had poor embryos after ooplasmic injection, but the donor embryo controls were also poor. The patients did not become pregnant and had no donor embryos frozen. Ooplasmic transfer at the MII stage may be promising in patients with compromised embryos; however, evaluation of ooplasmic anomalies and optimization of techniques will require further investigation prior to widescale application.

Cell Culture Techniques↗