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121.
Incidence of cancer in children born after in-vitro fertilization   总被引:4,自引:0,他引:4  
Evaluation of the long-term health of children born using in-vitro fertilization (IVF) provides important information to clinicians and consumers. Until very recently, there have been no published data on the incidence of cancer in children conceived as a result of IVF, despite a number of case reports of neuroblastoma in children conceived using fertility drugs. This study used a record-linkage cohort design to investigate the incidence of cancer in children born after IVF. The study included all conceptions using assisted reproductive technologies between 1979 and 1995 at two clinics in Victoria, Australia that resulted in a live birth. Data on births were linked with a population-based cancer registry to determine the number of cases of cancer that occurred. The standardized incidence ratio (SIR) was calculated by comparing the observed number of cases to the expected number of cases. The final cohort included 5249 births. The median length of follow-up was 3 years, 9 months (range 0-15 years). In all, 4.33 cases of cancer were expected and six were observed, giving a SIR of 1.39 (95% CI 0.62-3.09). This study found that children conceived using IVF and related procedures did not have a significantly increased incidence of cancer in comparison to the general population.  相似文献   
122.
Between October 1998 and January 1999, we examined the influence of ultrasound guidance in embryo transfer on pregnancy rate in 362 patients from our in-vitro fertilization (IVF)-embryo transfer programme. These patients were prospectively randomized into two groups: 182 had ultrasound-guided embryo replacement, and 180 had clinical touch embryo transfer. There were no statistically significant differences between the two groups with respect to age, cause of infertility and in the characteristics of the IVF cycle. The pregnancy rate was significantly higher among the ultrasound-guided embryo transfer group (50%) compared with the clinical touch group (33.7%) (P < 0.002). Furthermore, there was also a significant increase in the implantation rate: 25.3% in the ultrasound group compared with 18.1% in the clinical touch group (P < 0.05). In conclusion, ultrasound assistance in embryo transfer significantly improved pregnancy and implantation rates in IVF.  相似文献   
123.
Current ovarian stimulation regimens for IVF are complex and not without risk. Increasing our knowledge of the physiology of follicle development and dominant follicle selection may enable the design of less complex, safer and cheaper ovarian stimulation regimens for IVF. Decremental serum FSH concentrations during the follicular phase of the menstrual cycle are required for single dominant follicle selection. Only the most mature follicle will continue its development due to increased sensitivity for stimulation by FSH. FSH stimulation becomes insufficient for less mature follicles and remaining cohort follicles will therefore go into atresia. The number of days during which FSH is above the threshold for stimulation of follicle development is limited, resulting in a narrow FSH window. More medium sized and large pre-ovulatory follicles and increased oestradiol output can be induced by the administration of small doses of exogenous FSH during the mid- to late follicular phase, preventing the physiological decrease in FSH stimulation. Intervention with decremental serum FSH concentrations in combination with gonadotrophin-releasing hormone (GnRH) antagonists to prevent a premature rise in serum LH may induce ongoing growth of multiple follicles sufficient for IVF. The benefits and risks of these minimal hyperstimulation protocols require further evaluation.  相似文献   
124.
A multicentre, open-label, randomized study of the gonadotrophin-releasing hormone (GnRH) antagonist ganirelix (Orgalutran((R))/Antagon((TM))) was performed in women undergoing ovarian stimulation with recombinant FSH (rFSH: Puregon((R))). The study was designed as a non-inferiority study using a long protocol of buserelin (intranasal) and rFSH as a reference treatment. A total of 730 subjects was randomized in a treatment ratio of 2:1 (ganirelix:buserelin) using an interactive voice response system which stratified for age, type of infertility and planned fertilization procedure [IVF or intracytoplasmic sperm injection (ICSI)]. The median duration of GnRH analogue treatment was 5 days in the ganirelix group and 26 days in the buserelin group, whereas the median total rFSH dose was 1500 IU and 1800 IU respectively. In addition, in the ganirelix group the mean duration of stimulation was 1 day shorter. During ganirelix treatment the incidence of LH rises (LH >/=10 IU/l) was 2.8% versus 1.3% during rFSH stimulation in the buserelin group. On the day of triggering ovulation by human chorionic gonadotrophin (HCG), the mean number of follicles >/=11 mm diameter was 10.7 and 11.8, and the median serum oestradiol concentrations were 1190 pg/ml and 1700 pg/ml in the ganirelix and buserelin groups respectively. The mean number of oocytes per retrieval was 9.1 and 10.4 respectively, whereas the mean number of good quality embryos was 3.3 and 3.5 respectively. The fertilization rate was equal in both groups (62.1%), and the same mean number of embryos (2.2) was replaced. The mean implantation rates were 15.7% and 21.8%, and the ongoing pregnancy rates per attempt were 20.3% and 25.7% in the ganirelix and buserelin groups respectively. Evaluation of all safety data indicated that the ganirelix regimen was safe and well tolerated. The overall incidence of ovarian hyperstimulation syndrome was 2.4% in the ganirelix group and 5.9% in the reference group. The results of this study support a safe, short and convenient treatment regimen of ganirelix, resulting in a good clinical outcome for patients undergoing ovarian stimulation for IVF or ICSI.  相似文献   
125.
Gonadotrophin-releasing hormone agonists (GnRHa) are widely used in in-vitro fertilization (IVF) for the prevention of a premature rise in luteinizing hormone (LH) concentrations. However, the administration of GnRHa during the follicular phase may also impair subsequent luteal function due to retarded recovery of pituitary gonadotrophin secretion. Therefore, luteal supplementation is generally applied. The present study was designed to determine whether a premature LH surge would still be prevented after early cessation of GnRHa during ovarian stimulation and whether subsequent luteal phase LH production would be sufficient to support progesterone synthesis by the corpus luteum. Sixty patients were randomized for three groups: (i) A long GnRHa/human menopausal gonadotrophin (HMG) protocol with luteal support by repeated human chorionic gonadotrophin (HCG) (n = 20), (ii) early follicular phase cessation of GnRHa without luteal support (n = 20), and (iii) a long GnRHa protocol without luteal support (n = 20). Frequent ultrasound and blood sampling was performed during the entire IVF cycle. Forty normo-ovulatory women served as controls. No premature LH surges were found after early cessation of GnRHa. In this group, some pituitary recovery occurred during the late luteal phase, but this did not affect corpus luteum function. Progesterone concentrations were shown to be dependent on disappearance of the pre-ovulatory bolus of HCG. Pregnancies occurred in all three groups. In conclusion, early follicular phase cessation of GnRHa is still effective in the prevention of a premature rise in LH. Although some pituitary recovery was observed thereafter, corpus luteum function is still abnormal due to early luteolysis.  相似文献   
126.
The aim of this study was to estimate reliable cumulative probabilities of achieving an ongoing pregnancy after successive in-vitro fertilization or intracytoplasmic sperm injection (IVF/ICSI) cycles, according to a woman's age, subfertility diagnosis and primary or secondary subfertility. Therefore reasons for quitting treatment without achieving an ongoing pregnancy were taken into account. Moreover, we studied whether there were trends in cumulative probabilities after adjustment for potential confounding effects of the other two characteristics, duration of subfertility, year of first treatment and reason for quitting treatment. In total, 2984 IVF/ICSI cycles were performed in 1315 couples at the University Hospital Nijmegen, The Netherlands, between 1991 and 1998. The 'realistic' cumulative probability of achieving an ongoing pregnancy was 54.5% after five consecutive IVF/ICSI cycles, which was about 10% lower (absolute value) than the optimistic probability calculated by life-table analysis and about 10% higher (absolute value) than the most pessimistic estimate. Women of 35 years or younger had a higher probability of achieving an ongoing pregnancy than the older women. As ICSI is now an option, there were no obvious differences between the subfertility diagnosis subgroups. The cumulative probability after the first two IVF/ICSI cycles was higher in women with secondary subfertility than in those with primary subfertility; this advantage disappeared after further treatment. These trends remained valid after adjustment for confounding factors.  相似文献   
127.
Intercourse during an IVF cycle has the potential to improve pregnancy rates since exposure to semen is reported to promote embryo development and implantation in animals. Conversely, coitus-induced uterine contractions or introduction of infection may have a detrimental effect. A multicentre prospective randomized control trial was conducted to determine if intercourse during the peri-transfer period of an IVF cycle has any influence on pregnancy success. Participants undergoing thawed embryo transfer (Australian centre) or fresh embryo transfers (Spanish centres) were randomized either to abstain or to engage in vaginal intercourse around the time of embryo transfer. The transfer of 1343 embryos during 478 cycles of IVF resulted in 107 pregnancies (22.4%), with 125 viable embryos remaining by 6-8 weeks gestation. There was no significant difference between the intercourse and abstain groups in relation to the pregnancy rate (23.6 and 21.2% respectively), but the proportion of transferred embryos that were viable at 6-8 weeks was significantly higher in women exposed to semen compared to those who abstained (11.01 versus 7.69 viable embryos per 100 transferred embryos, P = 0.036, odds ratio 1.48, 95% confidence interval 1.01-2.19). Hence exposure to semen around the time of embryo transfer increases the likelihood of successful early embryo implantation and development.  相似文献   
128.
Several case reports have indicated that a small subgroup of patients may develop ovarian hyperstimulation following the administration of gonadotropin-releasing hormone agonists (GnRHa) without gonadotropins. However, since only few such cases have been published, it is unclear what course to follow in subsequent cycles after ovarian hyperstimulation in the first cycle using only GnRHa. A 33-yr-old woman was referred to in vitro fertilization for oocyte donation. A depot preparation (3.75 mg) of tryptorelin without gonadotropins induced ovarian multifollicular enlargement with high estradiol level, and was followed by human chorionic gonadotropin administration and oocyte retrieval. In a subsequent cycle of the same patient, a low dose of tryptorelin (0.05 mg) did not induce ovarian hyperstimulation, and resulted in clinical pregnancy. This report shows potential management of ovarian hyperstimulation following the administration of GnRHa without gonadotropins.  相似文献   
129.
目的探索在玻璃化冷冻技术基础上IVF周期中克罗米芬促排卵方案的临床效果及经济效益分析。方法 2006年度101个病例在知情同意下随机分为两组,CC组为国产克罗米芬、HMG并辅以GnRH拮抗剂预防LH峰的促排卵方案;GnRHa组为以常规的GnRHa降调和果纳芬、辅以少量国产HMG的促排卵方案为主;所获胚胎根据子宫内膜条件实施鲜胚移植或玻璃化冷冻复苏后移植,每个病例追踪到孩子出生或所有胚胎用完或本人放弃为止;分析两组得卵数、受精率、2PN率、卵裂率、优良胚胎率、取卵周期活婴分娩率、促排卵药费、周期平均总费用以及每获得一次活婴分娩的平均费用等参数。结果 CC和GnRHa组平均得卵数分别为7.46±4.04和10.19±3.95枚,有极显著性差异;IVF/ICSI受精率分别为85.1%/88.3%和68.3%/76.0%,有极显著性差异;促排卵药费、周期平均总费用以及每获得一次活婴分娩的平均费用分别为1779.65±1123.59元、11008.81±2987.36元、27447.67±7164.10元和9241.62±2883.20元、19393.87±3297.55元、48946.43±8322.38元,组间有极显著性差异,差异因素来源于促排卵药费;2PN率、卵裂率、优良胚胎率、冻胚移植胚胎植入率、取卵周期活婴分娩率分别为84%、97.4%、85.4%、29.1%、37.5%和79%、96.5%、83.3%、34.7%、39.6%,两组间无显著性差异;两组均无熟前LH峰和严重并发症发生事件。结论 IVF中使用克罗米芬联合HMG和GnRH拮抗剂促排卵,结合胚胎玻璃化冷冻技术是一种安全、高效和经济的治疗策略。  相似文献   
130.
PurposeWe performed a systematic review and meta-analysis of available literature to investigate the efficacy of the intracytoplasmic sperm injection (ICSI) in couples with non-male factor with respect to the clinical outcomes.MethodsThe literature search was based on EMBASE, PubMed, and the Cochrane Library. All studies published after 1992 until February 2020 and written in English addressing patients in the presence of normal semen parameters subjected to ICSI and in vitro fertilization (IVF) were eligible. Reference lists of retrieved articles were hand-searched for additional studies. The primary outcomes were fertilization rate, clinical pregnancy rate, and implantation rate; the secondary outcomes were good-quality embryo rate, miscarriage rate, and live birth rate.ResultsFour RCTs and twenty-two cohort studies fulfilling the inclusion criteria were included. Collectively, a meta-analysis of the outcomes in RCTs showed that compared to IVF, ICSI has no obvious advantage in fertilization rate (RR = 1.16, 95% CI: 0.83–1.62), clinical pregnancy rate (RR = 1.04, 95% CI: 0.66–1.64), implantation rate (RR = 1.12, 95% CI: 0.67–1.86), and live birth rate (RR = 1.17, 95% CI: 0.43–3.15). Pooled results of cohort studies demonstrated a statistically significant higher fertilization rate (RR = 1.16, 95% CI: 1.03–1.31) and miscarriage rate (RR = 1.04, 95% CI: 1.01–1.06) in the ICSI group; furthermore, higher clinical pregnancy rate (RR = 0.85, 95% CI: 0.77–0.94), implantation rate (RR = 0.78, 95% CI: 0.65–0.95), and live birth rate (RR = 0.86, 95% CI: 0.79–0.94) was founded in the IVF group; no statistically significant difference was observed in good-quality embryo rate (RR = 0.98, 95% CI: 0.93–1.04).ConclusionICSI has no obvious advantage in patients with normal semen parameters. Enough information is still not available to prove the efficacy of ICSI in couples with non-male factor infertility comparing to IVF.Electronic supplementary materialThe online version of this article (10.1007/s10815-020-01970-9) contains supplementary material, which is available to authorized users.  相似文献   
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