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PURPOSE: The objective of our study is to investigate the optimum number of stimulated intrauterine insemination (SIUI) or donor insemination (DI) cycles that can be offered to the couples prior to in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) in a tertiary referral unit for assisted reproduction. METHODS: This is a retrospective analysis of 408 SIUI and 704 DI cycles performed in a tertiary referral unit for assisted reproduction. SIUI's were performed by controlled ovarian hyperstimulation and ovulation induction followed by insemination 36 h later. DI's were performed in natural or stimulated cycles after thawing frozen donor sperm. The main outcome measured was cumulative live birth rate (CLBR) per couple. RESULTS: A maximum CLBR of 26.1% was achieved after the fourth cycle of SIUI. The CLBR of DI increased to 60.1% in the sixth cycle. CONCLUSIONS: This study, in line with a number of other studies, is unable to demonstrate unequivocally whether increasing numbers of IUI or DI cycles are justified clinically or financially. There is a need for larger datasets from multiple centres along with rigorous randomised trials to compare treatment pathways. Until then, the resources spent on the provision of extra SIUI cycles may be better utilized by early referral to IVF.  相似文献   
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A supportive approach to care for women during the second stage of labor that primarily relies on the laboring woman's involuntary expulsive urges has been advocated. We aimed to learn about the clinical circumstances surrounding the caregiver shift from being primarily supportive to directing women regarding their bearing-down efforts. This research analyzed the communications of 10 birth attendants and women during the expulsive phase of labor using videotapes recorded from two studies carried out between 1986 and the present. The occasions when a birth attendant shifted verbalizations were identified, and categories of the rationales that may have influenced the modification in caregiver behavior were developed. Birth attendants most frequently provided directions to help the woman push effectively, that is, to focus the woman's bearing-down efforts during maternal distress, fatigue, fear, and pain to expedite the labor process (38% of the occasions of caregiver change in verbalizations). The next most frequent clinical situations when caregivers offered directions about "pushing" were diminished urge to bear-down with epidural analgesia (10%), routine arbitrary practices (9% caregiver and 6% by supportive companion), and fetal distress (<1%). A category of "supportive direction" (20%) was identified. This care strategy has not been previously reported. It combined direction with support in a way that was supportive rather than overriding the woman's involuntary efforts.  相似文献   
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On September 21 and 22, 2006, the National Institute of Child Health and Human Development of the National Institutes of Health sponsored a 2-day workshop titled "Preeclampsia--A Pressing Problem." The purpose of the workshop was to bring together leaders in the field to present and discuss their diverse research areas, which ranged from basic science to clinical trials and management, and to identify scientific gaps. This article is a summary of the proceedings of that workshop. Although much progress is being made in understanding the underpinnings of preeclampsia, a number of research gaps are identified that, if filled, would hasten progress in the field. It is the overall consensus that preeclampsia is a multifactorial disease whose pathogenesis is not solely vascular, genetic, immunologic, or environmental but a complex combination of factors. In addition, a number of specific scientific gaps are identified including insufficient multidisciplinary and collaborative research, clinical trials and studies of patient management, and a lack of in-depth mechanistic research. The research community needs to focus on these gaps to better understand the disease, with the ultimate goal of preventing the disorder.  相似文献   
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