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1.
The birth of 12 healthy infants to fathers with non-mosaic Klinefelter's syndrome has been reported so far. The spermatozoa for these pregnancies was obtained from frozen-thawed ejaculate in one pregnancy (twins) and from the testis in the remaining 10 infants. All of them had a normal karyotype. We describe a patient with non-mosaic Klinefelter's syndrome from whom a testicular biopsy was obtained and motile spermatozoa were collected. Of 16 oocytes that were injected, 14 fertilized and cleaved. Three embryos were transferred, resulting in a triplet pregnancy. Karyotype analysis from chorionic villous sampling revealed 46,XX, 46,XY and 46,XXY from the three fetuses. The affected 46,XXY fetus was reduced on the 14th gestational week. The pregnancy culminated with the birth of a healthy male and female, on the 36th gestational week, weighing 3600 and 2660 g respectively. This case report proves the presence of hyperploid spermatozoa in the seminiferous lumen, and strengthens the necessity of genetic diagnosis of the embryos or fetuses in such pregnancies to fathers with non-mosaic Klinefelter's syndrome.  相似文献   
2.
Coasting is a method to decrease the incidence of ovarian hyperstimulation syndrome (OHSS), which involves withdrawing exogenous gonadotrophins until the serum estradiol (E(2)) level decreases. The application of this strategy, as it appears in the literature, has been variable, with heterogeneous criteria for initiating and ending the coasting process and as a result, reports of efficacy are inconsistent. In attempt to establish a recommended protocol for coasting we reviewed and analysed 10 relevant studies, found by a Medline search. Based on the data collected, coasting should be initiated when the serum E(2) concentration exceeds 3000 pg/ml, but not unless the leading follicles reach a diameter of 15-18 mm. Its duration should be limited to <4 days, thus, preventing the decrease in implantation and pregnancy rates that occur after longer periods of coasting. Administration of hCG should be withheld until serum E(2) falls below 3000 pg/ml. Based on the published data, these suggested guidelines result in an acceptably low incidence of severe OHSS (<2%) and provide satisfactory fertilization and pregnancy rates (55-71% and 36.5-63% respectively). A multicentre randomized prospective study would help to confirm the effectiveness of this approach.  相似文献   
3.
Induction of ovulation after gnRH antagonists   总被引:2,自引:0,他引:2  
The gonadotrophin-releasing hormone (GnRH) antagonist binds competitively to the receptors and thereby prevents endogenous GnRH from exerting its stimulatory effect on the pituitary cells. This causes suppression of gonadotrophin secretion which occurs immediately after administration of the antagonist. When using GnRH antagonist in controlled ovarian stimulation, ovulation or maturation of the oocyte can, therefore, be induced by a variety of drugs, e.g. native GnRH, recombinant LH or short-acting GnRH agonists. Short-acting GnRH agonists were recommended for triggering ovulation in cases with a high risk of developing ovarian hyperstimulation syndrome (OHSS). Since it is evident that GnRH is required to initiate the LH surge and the oestradiol rise, a single administration of GnRH antagonist during the late follicular phase delays the LH surge. Studies showed that a single s.c. administration of 3 or 5 mg of Cetrorelix in the late follicular stage was sufficient to prevent the LH surge for 617 days. This phenomenon can be used in high responder patients who are prone to OHSS. The question whether this delay has any effect on oocyte quality and maturation still remains unanswered. Overall, there are four uses for GnRH antagonist: (i) using short-acting GnRH agonists for triggering ovulation in cases in which the GnRH antagonist is part of the protocol for ovarian stimulation. Recombinant LH and native LHRH could also be used as triggers of LH surge; (ii) delaying the LH surge in cases prone to OHSS by treatment with GnRH antagonist; (iii) to administer GnRH antagonist during the luteal phase to decrease the activity of corpora lutea; (iv) in polycystic ovarian disease with elevated LH the LH/FSH ratio can be corrected with the injection of GnRH antagonist prior to and during ovarian stimulation.  相似文献   
4.
PROBLEM: To examine the relationship between the concentration of uterine fluid human decidua-associated protein (hDP) 200, identified as a monoclonal rheumatoid factor, and different phases of the menstrual cycle. METHODS: Sequential measurements of hDP 200 concentration in uterine fluid were performed in 11 normal ovulatory women, aged 22–36 years. The samples were collected in early proliferative phase, late proliferative phase, periovulatory period, early secretory phase, and late secretory phase. RESULTS: Consistent fluctuations of hDP 200 levels in uterine fluid were found throughout the menstrual cycle. High levels were found during early proliferative phase and periovulatory period related to significantly lower levels during late proliferative and early luteal phases. CONCLUSION: There is menstrual phase dependent variation in the uterine fluid levels of hDP 200.  相似文献   
5.
A 3 year retrospective analysis was conducted of pregnancies achieved after various assisted reproductive treatment modalities in our infertility practice, to calculate and compare the rates of monozygotic twinning (MZT). A total of 731 pregnancies achieved after various assisted reproduction treatments were reviewed. Gonadotrophin therapy for induction of ovulation and controlled ovarian hyperstimulation (COH) yielded 129 clinical pregnancies. Conventional IVF yielded 139 pregnancies. IVF and intracytoplasmic sperm injection (ICSI) with or without assisted hatching (AH) yielded 463 pregnancies, all during the same time period. The rates of multiple pregnancy (monozygotic and dizygotic) twins and triplets were recorded. MZT was found in 1.5% of ovulation induction or COH pregnancies (2/129). The incidence of MZT after conventional IVF was 0.72% (1/139). After IVF-ICSI/AH, MZT was found in 0.86% (4/463). The overall rate of MZT was 0.95% (7/731). Five cases were dizygotic triplets and two cases were monozygotic twins. We found the rate of MZT after assisted reproduction treatment increased more than two-fold over the background rate in the general population. Dizygotic triplets were found more often than monozygotic twins. The rate of MZT was consistently increased, irrespective of treatment modality or micromanipulation. This may signify that the aetiology of increased MZT after assisted reproduction is the gonadotrophin treatment rather than in-vitro conditions, micromanipulation, or multiple embryo transfer.  相似文献   
6.
Intracytoplasmic sperm injection in the mouse   总被引:9,自引:0,他引:9  
Intracytoplasmic sperm injection (ICSI) into mouse oocytes involvesa very low survival rate. This study was designed to determinewhy ICSI frequently fails in mice. Metaphase II oocytes wereobtained from superovulated 4–6 week old F1 hybrid mice.Spermatozoa were retrieved from the epididymis of 12–14week old F1 hybrid mice. The spiked microinjection pipette usedto inject a spermatozoon into the ooplasm had outer and innerdiameters of 10 and 8 µm respectively. The oocytes usedin the first part of the study were not activated (group 1).Some oocytes were incubated with calcium ionophore for 5 min(group 2). The injected oocytes were evaluated 6, 20, 48 and72 h after injection. A total of 143 eggs in each group underwentICSI. In group 1, sperm heads escaped into the perivitellinespace. In all, 63 (47%) of the remaining oocytes were damagedduring the injection or had degenerated by the first evaluation.The survival rate was 53%, but fertilization did not occur.In group 2, 31 oocytes (22%) were damaged during microinjectionor soon degenerated. Two oocytes underwent accidental subzonalinsemination. Six oocytes were fertilized (4.2%) among the 78%of survivors. After injection, the sperm tail was found in thecytoplasm (27 and 31% in groups 1 and 2 respectively), the perivitellinespace (45% in both groups) or protruding through the zona pellucida(28 and 23% respectively). More oocytes degenerated when thetail remained in the cytoplasm, i.e. 78% in group 1 and 36%in group 2.  相似文献   
7.
Objective: To compare the outcome of intracytoplasmic sperm injection (ICSI) with fresh and frozen-thawed testicular spermatozoa in patients with nonobstructive azoospermia.Design: Retrospective analysis of consecutive ICSI cycles.Setting: In Vitro Fertilization Unit, Assaf Harofeh Medical Center.Patient(s): Eighteen with nonobstructive azoospermia in whom testicular sperm was found after testicular sperm extraction.Intervention(s): Testicular sperm retrieval, cryopreservation, and ICSI with fresh or frozenthawed testicular spermatozoa.Main Outcome Measure(s): Two-pronuclear fertilization; embryo cleavage rates, mean number of embryos transferred per cycle, and their relative quality, embryo implantation, clinical pregnancy, and ongoing pregnancy rates (PRs) per ET.Result(s): No statistically significant differences were noted in all parameters examined between ICSI cycles with fresh or cryopreserved testicular spermatozoa from the same nine patients and comparing all ICSI cycles performed; with fresh (25 cycles) and thawed (14 cycles) testicular spermatozoa, respectively: two-pronuclear fertilization, 47% versus 44%; embryo cleavage rates, 94% versus 89%; implantation rates, 9% versus 11%; and clinical PR, 26% versus 27%. The delivery or ongoing PR using fresh sperm was better (21% versus 9%), but the difference did not reach statistical significance. The cumulative clinical PRs and ongoing PRs per testicular sperm extraction procedure were 36% and 24%, respectively.Conclusion(s): Testicular sperm cryopreservation using a simple freezing protocol is promising in patients with nonobstructive azoospermia augmenting the overall success achieved after surgical sperm retrieval. (Fertility Sterility 1997;68:892-7. C 1997 by American Society for Reproductive Medicine.)  相似文献   
8.
9.
BACKGROUND: Poor sperm morphology is statistically associated with an increase in the incidence of chromosome abnormalities. Our aim was to examine the possible correlation between chromosomal aberrations and sperm morphology in the same cell. METHODS: 12349 spermatozoa from 7 teratozoospermic and one globozoospermic patients, and from 3 fertile donors were analyzed using a system which scans for cell morphology and chromosomal ploidy in the same cell using digital technology. RESULTS: Chromosomal aberrations were detected in 5.3% of teratozoospermic cases and in 6.7% in the globozoospermic patient compared with 1.6% in donors (P < 0.0001). Chromosomal aberrations were more common in abnormally formed sperm compared with normal spermatozoa: 4.5% vs 1.3% in the teratozoospermic group and 2.0% vs 0.3% in the control group (NS), especially frequent among sperm with two heads or two tails (52.1-77.2%) or extreme head deformations (10.6-11.1%) irrespective of grouping, and in mild amorphous heads in the globozoospermic patients (20.2%). The frequency of chromosomal aberrations in morphologically normal sperm was comparable whether derived from teratozoospermic or normospermic patients. CONCLUSIONS: The computerized cell-scanning system demonstrated the relationship between chromosomal aberrations and sperm morphology in the same spermatozoon. The incidence of chromosomal aberrations was positively linked to abnormal sperm morphology, the more severe the abnormality, the higher the incidence of aneuploidy.  相似文献   
10.
The timing of ET was evaluated by transferring four embryos at 44 to 48 hours, 68 to 72 hours, or equally dividing and sequentially transferring at 44 to 48 and 68 to 72 hours after insemination. Fifty-one patients were randomly allocated to one of the above protocols. The mean number of blastomeres of embryos transferred at 68 to 72 hours after insemination was significantly (P less than 0.0001) higher than those transferred at 44 to 48 hours. The number of embryos with good morphology was similar in all study groups. The pregnancy rate was similar in the three protocol groups, 53% at 44 to 48 hours, 59% at 64 to 72 hours, and 47% by sequential transfer. There probably is no advantage in delaying the transfer or dividing the embryos into two sequential transfers. It seems that sequential transfer is not associated with any harmful effect.  相似文献   
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