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Objective To investigate obstetric outcomes in singleton pregnancies conceived by in vitro fertilization (IVF) to nulliparous women older than 35 compared to those of their younger counterparts. Methods Nulliparous women 35 years and older at delivery conceived by IVF (n = 89) were compared with nulliparous women 34 years and younger at delivery conceived by IVF (n = 48). Data included antenatal data, gestational age at delivery, maternal and neonatal complications and mode of delivery. Results The incidence of pregnancy-induced hypertension in the younger group was significantly higher than that in the elderly group (13 vs. 3.4%, P = 0.043). There were no measurable differences in other obstetric outcomes such as placental abnormality, premature delivery or neonatal asphyxia between the two groups. Conclusion The current results suggest that obstetric complications in pregnancies conceived IVF are attributed to mechanisms other than those depend on advanced maternal age.  相似文献   
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Purpose To explore the prevalence, predictor of clinical pregnancy and possible aetiology of poor ovarian response (POR) in in vitro fertilization–embryo transfer (IVF–ET) in Chinese. Methods A total of 4,600 retrieval oocyte cycles were finished between July 1, 2004 and April 30, 2006. Poor ovarian responses were observed in 426 patients of 472 cycles undergoing IVF, which were selected on the same retrieve oocyte day as the control group. The outcome of IVF–ET and the common markers of ovarian reserve were compared. Results The patients had previous ovarian surgery in 64 cycles of 472 poor ovarian response cycles. The group with poor ovarian response has significant differences in comparison with the control group in age (36.6 ± 4.2 vs 33.3 ± 4.04), ovarian surgeries (13.6 vs 2.8%), dose of gonadotrophin (58.5 ± 15.8 vs 40.6 ± 17.0), fertilization rate (71.5 vs 86%) and pregnancy rate (14.8 vs 36.7%). In the group with poor ovarian responses, clinical pregnancy rate declined significantly in women aged >40 years than in those aged ≤40 years (2.8 vs 18.5%, P < 0.001). The age, basal serum follicle stimulating hormone (FSH), basal serum luteinizing hormone (LH), basal oestradiol (E2) concentrations, FSH to LH ratio and the antral follicle count (AFC) are the common markers of ovarian reserve in our center. We found that there were significant differences in age, basal FSH, FSH-to-LH ratio and the antral follicle count. But no statistical significant differences were observed in basal oestradiol concentration and basal serum LH when comparing the two groups. Binary logistic regression analysis was used to study the relation among age, FSH, LH, E2, AFC and clinical pregnancy, and the age (odds ratio, 0.863; 95% confidence interval, 0.805–0.925; p = 0.000) was the only variable selected. Conclusion Our data show that the prevalence of poor ovarian response in Chinese is 11.9%. Previous ovarian surgery is associated with poor ovarian responses. The pregnancy rate of women with poor ovarian response is low in IVF–ET, especially the decline in clinical pregnancy rate of women aged >40 years became accelerated. Correct identification of those who are at risk for POR prior to stimulation is helpful in tailoring the best stimulation protocol to individual patients. Chronological age significantly improved the prediction of clinical pregnancy of poor ovarian responders.  相似文献   
94.
Objective  The objective of this study was to assess the cost-effectiveness of different embryo transfer strategies for a single cycle when two embryos are available, and taking the NHS cost perspective.
Design  Cost-effectiveness model.
Setting  Five in vitro fertilisation (IVF) centres in England between 2003/04 and 2004/05.
Population  Women with two embryos available for transfer in three age groups (<30, 30–35 and 36–39 years).
Methods  A decision analytic model was constructed using observational data collected from a sample of fertility centres in England. Costs and adverse outcomes are estimated up to 5 years after the birth. Incremental cost per live birth was calculated for different embryo transfer strategies and for three separate age groups: less than 30, 30–35 and 36–39 years.
Main outcome measures  Premature birth, neonatal intensive care unit admissions and days, cerebral palsy and incremental cost-effectiveness ratios.
Results  Single fresh embryo transfer (SET) plus frozen single embryo transfer (fzSET) is the more costly in terms of IVF costs, but the lower rates of multiple births mean that in terms of total costs, it is less costly than double embryo transfer (DET). Adverse events increase when moving from SET to SET+fzSET to DET. The probability of SET+fzSET being cost-effective decreases with age. When SET is included in the analysis, SET+fzSET no longer becomes a cost-effective option at any threshold value for all age groups studied.
Conclusions  The analyses show that the choice of embryo transfer strategy is a function of four factors: the age of the mother, the relevance of the SET option, the value placed on a live birth and the relative importance placed on adverse outcomes. For each patient group, the choice of strategy is a trade-off between the value placed on a live birth and cost.  相似文献   
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Polycystic ovaries syndrome (PCOS) is one of the most common female hormonal disorders. Its multiple components--reproductive, metabolic, neoplasic and cardiovascular--have a major impact on the public health. Androgen excess and resistance to insulin, probably from genetic origin, are responsible for most of the clinical symptomatology. Resistance to insulin seems to be accompanied by a greater risk of glucose intolerance, type 2 diabetes, lipidic anomalies and can involve the development of cardiovascular diseases. In addition, sleep apnea syndrome is more progressively described in PCOS. Infertility, menses disorders and hirsutism often push these patients to consult their physician. A better understanding of the physiopathological mechanisms led to the emergence of new therapeutic options increasing the sensitivity to insulin. Besides the pregnancy wishes, cares aim to attenuate the marks of the hyper-androgenism (hormonal treatment and cosmetic) and to correct cardiovascular, respiratory and gynaecological risk factors. In case of infertility by anovulation, cares must be performed by trained experts to minimize the risk of ovarian hyper-stimulation syndrome and multiple pregnancies. A gradation from loose weight to clomiphene citrate ovulation induction, ovarian drilling, low dose gonadotropin, in vitro fertilisation, or in vitro maturation of oocytes should bring back good reproduction potential.  相似文献   
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In vitro fertilization (IVF) in women of advanced age (>42 years) represents only 5%, a comparatively minute part, of the national IVF experience in the United States (US). In view of evolving population dynamics, it, however, also represents proportionally a rather quickly expanding patient need. Because of access restrictions at many IVF programs, this market does not live up to its potential. As best demonstrated by the 2004 US National Summary and Fertility Clinic Report, which for the first time reported pregnancies and births above age 45 year, IVF in women of advanced reproductive age represents a cutting edge area of interest for improving current IVF outcomes. Access to IVF should, therefore, not be withheld based on female age and/or baseline FSH levels. Instead, a definition of acceptable minimal pregnancy and life birth rates could be used to define the limits of offered access to IVF, independent of age and/or baseline FSH levels.  相似文献   
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