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Biomedical subjects

L L Veeck

Publications and source records attributed to L L Veeck.

At least 37 records · Page 2Linked to original sources
PubMed1998

The use of intracytoplasmic sperm injection with electroejaculates from anejaculatory men.

Electroejaculation has been successfully used for sperm procurement in anejaculatory men desiring fertility. However, electroejaculates typically have normal sperm numbers but poor motility, morphology, and functional deficiencies. Here we report the pregnancy outcome of a series of couples undergoing combined electroejaculation and in-vitro fertilization (IVF) with intracytoplasmic sperm injection (ICSI). In all, 13 couples underwent a total of 18 cycles. The aetiologies of anejaculation included history of retroperitoneal lymph node dissection for testicular cancers, spinal cord injury and psychogenic causes. ICSI was performed on 192 oocytes, resulting in a fertilization rate of 75.5%. A total of 15 embryo transfers were performed using a total of 51 embryos. Clinical pregnancy rate, as defined by positive fetal heart rate(s) using vaginal sonography, was 55.6% per retrieval; implantation rate was 33.3% per embryo. These rates appear to be similar to those obtained in standard IVF for non-male factor infertility, or ICSI for male factor infertility. The use of ICSI for electroejaculates undoubtedly provides these couples with the highest chance of pregnancy.

Ejaculation↗
PubMed1997

Simultaneous detection of multiple gene expression in mouse and human individual preimplantation embryos.

OBJECTIVE: To detect simultaneously multiple gene expression in mouse and human individual embryos by reverse transcriptase-polymerase chain reaction. DESIGN: Transcripts involved in the insulin-like growth factor (IGF) system were detected in mouse and human preimplantation embryos. SETTING: An academic teaching hospital. MAIN OUTCOME MEASURE(S): Transcripts of the IGF family genes. RESULT(S): In the mouse, genes are expressed differentially and messenger RNA transcripts of maternal origin in nonfertilized ova decline gradually until the initiation of the embryonic genome transcription. Insulin-like growth factor-binding protein-2 (IGFBP)-2, -3, -4, and beta-actin transcripts appear to be initiated at the two- to four-cell stage, whereas IGFBP-1, -5, and -6 transcripts are initiated at later stages. Transcription, once initiated, appears to continue through to the blastocyst stage. In humans, almost all genes of the IGF system were expressed in preimplantation embryos. This is the first report of the assessment of IGF family transcripts in individual embryos, and introduces a novel method for research and clinical diagnosis of preimplantation embryos.

Actins↗
PubMed1997

Testicular sperm extraction with intracytoplasmic sperm injection for nonobstructive azoospermia.

OBJECTIVES: To provide fertility for men with nonobstructive azoospermia. METHODS: A retrospective review of treatment results at a university infertility center was undertaken. Sixteen couples entered an attempted in vitro fertilization (IVF)-intracytoplasmic sperm injection (ICSI) cycle for treatment of nonobstructive azoospermia. Each man was azoospermic, and the male factor diagnosis of nonobstructive azoospermia was made on testis biopsy for 14 men and on clinical grounds for 2 men. Sperm were retrieved by testicular biopsy on the day of oocyte retrieval. Results of testicular examinations, serum follicle-stimulating hormone levels, and testicular histology as well as evaluation of the success rates of sperm retrieval, fertilizations, and pregnancies were made. RESULTS: Sperm were extracted from testis biopsies in 10 of 16 (62%) testicular sperm extraction (TESE) attempts. For cycles in which sperm were retrieved, normal fertilizations were achieved for 51 of 98 (52%) mature oocytes injected with testicular sperm in 10 couples. Biochemical pregnancies were achieved for 6 of 16 (38%) couples, with clinical pregnancies during 5 of 16 (31%) attempts at sperm retrieval, and ongoing pregnancy and subsequent live delivery for 4 of 16 (25%) attempts. CONCLUSIONS; Pretreatment clinical parameters are unable to predict which men with nonobstructive azoospermia will have spermatozoa retrieved by TESE. When sperm are found, clinical pregnancies can occur for half (5/10) of these couples using TESE with ICSI, with ongoing pregnancy and delivery for 4 of 10 (40%). Many men with nonobstructive azoospermia will have retrievable sperm with testis biopsy that are suitable for ICSI; however, 6 of 16 (38%) couples will not have sperm retrieved with TESE and may undergo an unnecessary IVF procedure.

Adult↗
PubMed1997

Transfer of cryopreserved-thawed pre-embryos in a cycle using exogenous steroids without prior gonadotrophin-releasing hormone agonist suppression yields favourable pregnancy results.

We have analysed the use of a programmed cycle of administration of exogenous steroids without prior suppression with a gonadotrophin-releasing hormone agonist (GnRHa) for the transfer of cryopreserved-thawed pre-embryos. From July 1992 to June 1994, 199 cycles (162 patients) were studied. Pre-embryos had been previously cryopreserved at the pronuclear stage using 1.5 M 1,2-propanediol as a cryoprotectant. Preparation of the endometrium was achieved in a step-up regime with transdermal oestradiol patches (0.1 to 0.4 mg). Progesterone in oil (50 mg i.m.) was started on cycle day 13. Pre-embryos were thawed on day 14 and transferred on day 15 after evidence of survival and cleavage. The mean (+/- SD) age of patients undergoing transfer was 35.4 +/- 4.3 years. The mean number of pre-embryos thawed was 4.7 +/- 1.8 with a mean of 3.3 +/- 1.4 pre-embryos being transferred. Eight of the cycles demonstrated follicular development >16 mm prior to thaw and transfer; however, these patients did not demonstrate a luteinizing hormone surge. Mean endometrial thickness on day 13 was 10.8 +/- 2.1 mm. Overall pregnancy rate was 29.2% (57/195). The ongoing or delivery rate was 16.1% (32/195). The rate of preclinical losses per transfer was 6.2% (12/195). Overall, the implantation rate was 6.2% (47/757). Thus, the use of a programmed cycle for cryopreserved embryo transfer yields favourable pregnancy outcome and offers practical advantages to patients. Prior suppression with a GnRHa is not necessary for endometrial preparation.

Adult↗
PubMed1997

Cryopreservation of all prezygotes in patients at risk of severe hyperstimulation does not eliminate the syndrome, but the chances of pregnancy are excellent with subsequent frozen-thaw transfers.

In-vitro fertilization patients (n = 15) at risk of ovarian hyperstimulation syndrome (OHSS) (oestradiol > or =4500 pg/ml on the day of human chorionic gonadotrophin administration and 25 or more follicles of intermediate or large size) underwent aspiration of all follicles and cryopreservation of all fertilized oocytes at the pronuclear stage. Patients were monitored for up to 2 weeks post-retrieval. Subsequent transfer of cryopreserved-thawed embryos was performed in programmed cycles using exogenous oestrogen and progesterone for endometrial preparation. Two patients (13%) developed OHSS necessitating hospitalization and vaginal aspiration of ascitic fluid. Two other patients (13%) developed moderate OHSS requiring ascitic fluid vaginal aspiration in the office setting, with dramatic improvement of the condition. Subsequent transfer of cryopreserved-thawed embryos yielded a clinical pregnancy rate of 58% per transfer and ongoing or delivery rates of 42 and 67% per transfer and per patient respectively. By eliminating pregnancy potential with cryopreservation of all prezygotes and examining the pregnancy potential with subsequent cryopreserved-thawed transfers, it is concluded that OHSS is reduced, but not eliminated for patients at risk. Subsequent transfer of cryopreserved-thawed prezygotes in a programmed cycle with exogenous steroids yields an excellent pregnancy rate.

Adult↗
PubMed1997

Expression of IGFs and their receptors is a potential marker for embryo quality.

PROBLEM: Insulin-like growth factors (IGFs) and insulin have been demonstrated to stimulate oocyte maturation and embryo development. Therefore, the expression of IGFs and their receptors may be an important intrinsic factor for embryo growth and may be a potential marker for embryo quality. METHOD OF STUDY: Thirty donated day 3 embryos were cultured in vitro for an additional 3 days to observe their developmental potential and were semiquantitatively analyzed for the expression of IGF-I, IGF-II, IGF-IR, IGF-IIR, and insulin-R. RESULTS: Our results show that the activity of these gene expressions correlates well with the morphological assessment and that high and more gene expressions were often associated with embryos of high growth potential. CONCLUSION: The IGF system may indeed play an important role in human embryogenesis; IGF gene expressions can be a good indicator of embryonic developmental stage and/or growth potential; finally, the IGF system can serve as a marker for embryo quality.

Base Sequence↗
PubMed1996

Use of a specific zona pellucida (ZP) protein 3 antiserum as a clinical marker for human ZP integrity and function.

OBJECTIVE: To evaluate binding characteristics of a specific zona pellucida (ZP) protein 3 (ZP3) antiserum to human oocytes in order to determine its usefulness as a clinical marker for human ZP integrity and function and its correlation with IVF outcome. DESIGN: Prospectively designed, blinded, internally controlled study. SETTING: Tertiary care academic center. PATIENTS: Patients undergoing IVF therapy who had either total failed fertilization or partial fertilization were studied. INTERVENTIONS: Metaphase II oocytes showing absence of pronuclear formation were salt stored 48 hours after insemination and bisected into matching hemizonae using micromanipulation. One hemizona was incubated with AS ZP3-6 (an antiserum generated against a synthetic ZP3 peptide derived from an amino acid sequence that is highly conserved in the structure of ZP3), whereas the matching hemizona was incubated with AS ZP3-7, an antiserum detecting exclusively mouse ZP3 (internal, negative control). Antibody binding was visualized using the peroxidase-antiperoxidase method and diaminobenzidine as color reagent. RESULTS: A total of 104 unfertilized oocytes were evaluated. Analysis of variance showed a significant interaction between gamete factor groups (sperm and oocyte) and antiserum factor. Patients with oocyte factor had significantly lower mean staining scores for the AS ZP3-6-treated hemizonae than patients with sperm factor. CONCLUSIONS: These results demonstrate that anomalies of human ZP3 can be identified with AS ZP3-6 and that these ZP abnormalities correlate with fertilization failure during IVF treatment. Thus, this newly developed biomarker may be of clinical significance in the identification of oocyte defects that are associated with fertilization disorders and may help in the decision-making process in the IVF-assisted fertilization setting.

Adult↗
PubMed1996

Messenger ribonucleic acid kinetics in human oocytes--effects of in vitro culture and nuclear maturational status.

OBJECTIVE: To study the effects of different nuclear maturational status (prophase I [PI] versus metaphase II [MII]) and in vitro culture on the kinetics of maternal messenger ribonucleic acid (mRNA) in human oocytes. DESIGN: Molecular biology on excess oocytes obtained from our clinical IVF program. INTERVENTIONS: The oocytes, classified as either PI or MII at collection, were used as such or cultured in vitro for an additional 24 hours. The relative levels of c-mos and cyclin-B1 were measured using semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR). RESULTS: The mean levels of c-mos and cyclin-B1 transcripts were indistinguishable between the PI, MII, PI oocytes matured in vitro, PI oocytes failing to mature, and MII oocytes cultured for additional 24 hours. The variability in the levels of these transcripts increased during the vitro culture. CONCLUSIONS: The level of c-mos and cyclin-B1 transcripts were not different in PI versus MII oocytes, therefore, differences seen in the clinical outcome of PI and MII oocytes may be unrelated to levels of these gene products. C-mos and cyclin B1 mRNA were maintained in vitro, thus degradation of maternal RNA is not activated in excess during the 24-hour culture.

Base Sequence↗
PubMed1996

Suppression and flare regimens of gonadotropin-releasing hormone agonist. Use in women with different basal gonadotropin values in an in vitro fertilization program.

OBJECTIVE: To evaluate the suppression and flare regimens of gonadotropin-releasing hormone agonist (GnRH-a) in ovarian hyperstimulation in women with variable basal gonadotropin values in an in vitro fertilization (IVF) program. STUDY DESIGN: A retrospective study comparing the initiation of GnRH-a in the midluteal phase of the preceding cycle (suppression protocol) and follicular phase of the stimulated cycle (flare protocol) in women with basal follicle-stimulating hormone (FSH) values < 15 mIU/mL and > or = 15 mIU/mL. RESULTS: The pregnancy rate per initiated cycle and implantation rate for women with basal FSH levels > or = 15 mIU/mL were 20.4% and 9.8% in flare GnRH-a cycles and 11.7% and 3.5%, respectively, in suppression GnRH-a cycles. Comparing the percent differences in clinical pregnancy and implantation rates between both protocols for women with different basal FSH values, pregnancy outcome was significantly greater in the flare protocols in women with values > or = 15 mIU/mL (P < .001). Individualization of the stimulation protocol by retrospective sorting of women undergoing IVF with respect to their basal gonadotropin levels significantly improved clinical pregnancy (P < .05) and implantation rates (P < .05) and reduced the cancellation rate (P < .05). CONCLUSION: The flare regimen with GnRH-a is a useful alternative for controlled ovarian hyperstimulation in women with elevated basal FSH values (> or = 15 mIU/mL) undergoing IVF.

Adult↗
PubMed1995

Low-dose glucocorticoids after in vitro fertilization and embryo transfer have no significant effect on pregnancy rate.

OBJECTIVE: To determine the effect on pregnancy rate (PR) of low-dose glucocorticoid treatment in cycles without micromanipulation. DESIGN: Randomized, prospective, double-blinded, placebo-controlled trial. SETTING: One university-based tertiary infertility center and two private infertility centers. PATIENTS: All patients receiving standard stimulation IVF-ET or transfer of cryopreserved embryos at the participating facilities from January to September 1993 were asked to participate in this study. Patients having micromanipulation were excluded from this study. INTERVENTIONS: Participating patients were randomized to either 16 mg oral 6-alpha-methylprednisolone for four evenings starting the evening of retrieval or the evening before thawing cryopreserved embryos or to placebo administered in an identical fashion. Both groups were treated with 250 mg oral tetracycline four times per day starting with initiation of the study medication and continuing for 4 days. Cryopreservation and stimulation cycles were managed according to pre-established protocols for all patients. A clinical pregnancy was confirmed by an appropriately rising hCG titer and a gestational sac on ultrasound. RESULTS: A total of 206 stimulation patients and 61 cryopreservation patients were randomized and had an ET. Patient characteristics were similar between groups. The clinical pregnancy and implantation rates between placebo and glucocorticoid groups were 35.9% versus 40.8% and 12.8% versus 11.7% for stimulation cycles and 30.3% versus 25% and 9.9% versus 7.4% for cryopreservation cycles, respectively. None of these differences were statistically significant. CONCLUSIONS: Glucocorticoid plus antibiotic treatment at these doses for transfers of nonmicromanipulated embryos does not appear to have a significant effect on pregnancy or implantation rates.

Adult↗
PubMed1995

Evaluation of the spindle apparatus of in-vitro matured human oocytes following cryopreservation.

The present study was conducted to determine if the cryopreservation of immature human oocytes has a deleterious effect on the meiotic spindle following maturation in vitro. Oocytes were obtained in excess from in-vitro fertilization patients and divided into four groups. Groups 1 (n = 98) and 2 (n = 80) consisted of immature oocytes cryopreserved before or after maturation in vitro respectively. Groups 3 (n = 37) and 4 (n = 9) served as non-frozen controls and included oocytes matured in vitro and in vivo respectively. The meiotic spindle was identified after incubation in anti-tubulin monoclonal antibody (1 h, 37 degrees C) and fluorescein-conjugated goat anti-mouse immunoglobulin G (IgG) (1 h, RT). Chromosomes were counterstained with 4',6'-diamidino-2-phenylindole. Following cryopreservation, group 1 oocytes demonstrated a 63% survival rate and 68% maturation rate in vitro. In all, 58% of the oocytes in group 2 survived the thaw. The number of oocytes with normal spindles in group 1 (81.0%) was not significantly different from control groups 3 (83.8%) and 4 (88.9%), while the number of group 2 oocytes with normal structures (43.5%) was significantly lower than groups 1 (P = 0.0004), 3 (P = 0.0002), and 4 (P = 0.025). These results suggest that cryopreservation of the prophase I human oocyte does not significantly increase abnormalities in the resulting meiotic spindle.

Cell Survival↗
PubMed1995

Cryopreservation: the problem of evaluation.

A simple evaluatory formula for reporting pregnancy rates involving cryopreserved material has so far remained elusive. It is highly desirable to have a method which would allow not only an evaluation of cryotechnology per se, but also an evaluation of the role of cryotechnology in enhancing the total reproductive potential of a single cycle. In this paper, nine separate formulae are described which can be used for the evaluation of cryopreservation. It is concluded that none of the existing formulae used alone expresses the total potential of cryopreservation, and that while each formula provides information regarding some aspect of the role of cryopreservation, the most comprehensive evaluation requires the answer to five different equations. The other four formulae, while often used, are regarded as providing information which is unsubstantiated or does not allow complete evaluation.

Cryopreservation↗
PubMed1994

Fertilization and in vitro development of cryopreserved human prophase I oocytes.

OBJECTIVE: To determine the potential for in vitro maturation, fertilization, and cleavage after cryopreservation of immature, prophase I human oocytes. DESIGN: Immature oocytes obtained in excess of the number required by the patient were randomized and cryopreserved at the prophase I stage or cultured as control. After thawing and maturation in vitro, test and control oocytes were inseminated with husband's sperm and evaluated for fertilization and cleavage in vitro. SETTING: In vitro fertilization program. PATIENTS: Consenting patients undergoing controlled ovarian hyperstimulation for the purposes of IVF. MAIN OUTCOME MEASURES: Rates of maturation to metaphase II, fertilization, and cleavage were compared between control and cryopreserved oocytes. RESULTS: Upon thaw, 58.5% (72/123) of prophase I oocytes were viable. Control oocytes demonstrated a 74.8% (98/131) maturation rate to metaphase II, a 56.5% (52/92) fertilization rate, and an 11.5% (6/52) blastocyst rate. Cryopreserved oocytes showed a 83.3% (60/72) rate of maturation, a 57.7% (30/52) fertilization rate, and a 3.3% (1/30) blastocyst rate. No significant differences were noted between any of these parameters. CONCLUSIONS: These results demonstrate that prophase I oocytes from stimulated IVF cycles are able to survive cryopreservation and resume meiosis to achieve full nuclear maturation post-thaw. In addition, cryopreserved oocytes retain the same capacity for fertilization and development as control oocytes.

Adult↗
PubMed1994

Transfer of cryopreserved-thawed pre-embryos in a natural cycle or a programmed cycle with exogenous hormonal replacement yields similar pregnancy results.

OBJECTIVE: To examine the results of 7 years of thawed ET during natural or controlled cycles using exogenous steroids. DESIGN: Retrospective evaluation to compare implantation and pregnancy rates with two protocols for transfer of cryopreserved-thawed pre-embryos. SETTING: Tertiary care academic center. PATIENTS: From January 1987 to December 1993, 521 patients who were < 40 years of age underwent 628 thawed embryo transfers. MAIN OUTCOME MEASURE: Pregnancy and implantation rates per thawed embryo transfer cycle. RESULTS: A total 1,987 pre-embryos survived the thawing process and were used in 628 thaw-transfer cycles. Transfer was performed in a natural cycle 2 days after the LH peak or on day 17 of a programmed cycle using a GnRH-agonist and hormone replacement therapy protocol; 182 pregnancies were established (182/628; 29%). Similar pregnancy rates were seen in the natural cycle (112/398; 28%) and the programmed cycle (70/230; 30%). The implantation rates were similar in the two methods of transfer cycles (11.9% versus 10.3%, natural versus programmed cycle). There were no significant differences in clinical or ongoing pregnancy rates in a natural or programmed cycle, correcting for the number of cryopreserved-thawed pre-embryos transferred. Patient's age at the time of freezing and the number of cryopreserved-thawed pre-embryos transferred are more important determinants of pregnancy than the type of cycle in which transfer occurs. CONCLUSION: Transferring cryopreserved-thawed pre-embryos in a natural or programmed cycle yields similar pregnancy results.

Adult↗
PubMed1994

Cryopreservation of human prophase I oocytes collected from unstimulated follicles.

OBJECTIVE: To evaluate the cryopreservation of immature human oocytes obtained from unstimulated ovarian tissue. DESIGN: Immature prophase I oocytes were obtained from unstimulated follicles and were either cryopreserved or cultured as controls. Cryopreservation was performed in a programmable freezing machine using one of two protocols. Method I (n = 133) used a one-step addition of cryoprotectant followed by a slow freeze and thaw protocol. With method II (n = 95), the cryoprotectant was added in a stepwise manner with cryopreservation performed in the presence of 0.2 M sucrose followed by rapid freezing and thawing. SETTING: Basic research center at a medical school. PATIENTS: Patients undergoing oophorectomy for nonovarian pathology. MAIN OUTCOME MEASURES: Rates of survival and maturation to metaphase II were compared between control oocytes and oocytes cryopreserved with methods I and II. RESULTS: With method I, a survival rate of 15.6% was obtained with 58.3% of surviving oocytes reaching metaphase II after culture compared with 50.0% of nonfrozen control oocytes. Method II produced a survival rate of 43.3% with 27.3% maturing to metaphase II. Maturation of control oocytes for method II was 46.4%. Although the survival rate with method II was significantly higher than with method I, the rate of in vitro maturation to metaphase II showed no difference. CONCLUSIONS: These results demonstrate that human prophase I oocytes obtained from unstimulated antral follicles are capable of meiotic maturation after cryopreservation.

Cell Survival↗
PubMed1993

Basal follicle-stimulating hormone level and age affect the chance for and outcome of pre-embryo cryopreservation.

All IVF cycles in which subsequent transfers of thawed pre-embryos occurred were studied. Both age and basal (cycle day 3) FSH level are important determinants of the chance for cryopreservation and the performance of cryopreserved pre-embryos. Although there was no age or FSH level above which pregnancy with frozen pre-embryos was not possible, the chances clearly decline. Thus, consideration to transferring larger numbers of pre-embryos fresh should be given to women in the fifth decade and those with basal FSH > 15 IU/L.

Adult↗