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31.
目的 分析1990—2010年中国15~19岁女性青少年结婚和生育的地区不平等性。方法 利用1990—2010年三次全国人口普查汇总数据,计算中国15~19岁女性青少年的已婚率和生育率。将各省份人均国内生产总值(gross domestic product,GDP)作为社会经济发展水平指标,计算女性青少年已婚率和生育率的不平等绝对指数(slope index of inequality,SII)和集中指数(concentration index,CI),并建立线性回归模型衡量已婚率和生育率与人均GDP的关联。结果 1990—2000年,全国15~19岁女性的已婚率从4.7%下降至1.2%,但在2010年反弹至2.1%。生育率从1990年的22.0/1 000人下降至2000年的6.0/1 000人,2010年进一步下降为5.9/1 000人。1990年,15~19岁女性青少年已婚率和生育率地区层面的社会经济不平等性不具有统计学意义(SII和CI均P>0.05)。SII分析显示,2000和2010年,人均GDP最低人群的已婚率比最高人群分别高2.4%(95%CI:0.4~4.4)和2.3%(95%CI:0.3~4.2)。与此同时, 2000年和2010年人均GDP最低人群的生育率比最高人群分别高12.9/1 000人(95%CI:5.4~20.5)和9.3/1 000人(95%CI:4.6~14.0)。已婚的CI值在2000年和2010年分别为-0.32(P=0.02)和-0.17(P=0.03), 生育的CI值在2000年和2010年分别为-0.37(P<0.01)和-0.26(P<0.01)。2000年,人均GDP上升100%,已婚率平均下降1.4%(95%CI:0.1~2.7),生育率平均下降7.9/1 000人(95%CI:2.9~12.8)。2010年,人均GDP上升100%,已婚率平均下降1.5%(95%CI:0.1~2.9),生育率平均下降6.7/1 000人(95%CI:3.2~10.1)。结论 2000年和2010年存在女性青少年早婚早育地区层面的社会经济不平等性,生活在经济发展水平较低的女性青少年更容易早婚早育;减少收入不公平、增加对贫困地区的教育投资可能是改善早婚早育地区不平等的有效措施。  相似文献   
32.
33.

Purpose

Uncertainties remain regarding the clinical efficacy of ovarian tissue cryopreservation and grafting. We report a retrospective analysis of reproductive outcomes and lessons learnt following 55 ovarian tissue transplant procedures at our center from 2006 to 2019.

Methods

We analyzed variables related to graft success such as tissue volume, follicular density, total follicular volume, and age on the duration of graft function.

Results

Follicular density and total follicular volume correlate positively with duration of graft function. All clinical pregnancies in our cohort occurred in women who were aged 35 or less at the time of ovarian tissue cryopreservation.

Conclusion

Graft success, as determined by eventual pregnancy and the longevity of graft function, may be impacted by factors including age at cryopreservation, follicular density, and total follicular volume.
  相似文献   
34.
The presence of cytokines such as the tumour necrosis factoralpha (TNF) and interleukin 2 (IL2) in human spermatozoa isstill to be defined. The aim of this study was to measure theconcentration of both soluble factors in seminal fluid. Datafrom normal semen samples (n = 24) confirmed the presence ofIL2 (258 ± 84 fmol/ml corresponding to 953 ± 369fmol/total volume of ejaculate) and TNFa (62.2 ± 16.4fmol/ml corresponding to 231.3 ± 86 fmol/total volumeof ejaculate). A significant positive correlation (r = 0.59;P < 0.01) was observed between the TNFa and the IL2 concentrations.The concentrations of these cytokines were not related to spermparameters. In contrast, IL2 concentrations (196.9 ±60.4 fmol/ml; 686.2 ± 236.7 fmol/total volume of ejaculate)evaluated in 16 seminal fluids with identified bacterial agentswere lower than in the control group, whereas TNF concentrations(68.6 ± 12.3 fmol/ml; 241.3 ± 78.9 fmol/totalvolume of ejaculate) were not significantly different from thecontrols. Further studies are needed to determine the potentialrole of these cytokines in the physiology of semen and theirusefulness as indicators of reproductive pathology.  相似文献   
35.
Two methods of recruiting fertile male controls were evaluated and compared. The first group was recruited from the partners of women attending an antenatal clinic without obtaining details of their reproductive history. The second group was recruited after obtaining a detailed reproductive history from the couple and employing stringent entry criteria. Entry criteria for the second group included a length of exposure to the risk of pregnancy of not more than 12 months and no previous episode of involuntary infertility for either partner. There were significant differences between the distributions of semen parameters obtained from the two groups, indicating that the selection criteria for "fertile" men significantly influence results obtained and therefore that it is important to employ stringent criteria for the recruitment of fertile male controls. The group which was recruited by stringent criteria (mean length of exposure to the risk of pregnancy of 3 months) was characterised by a significantly higher median concentration of spermatozoa which exhibited slow linear or nonlinear motility. This confirms the findings of a previous study which suggested that slow linear or nonlinear motility are superior forms of spermatozoal motion.  相似文献   
36.
体外受精胚胎移植后妊娠结局分析   总被引:2,自引:0,他引:2  
目的 探讨通过体外受精 -胚胎移植妊娠妇女的妊娠结局。方法 对自 2 0 0 0年 9月~ 2 0 0 2年1 1月在我院实施IVF -ET的 75例患者 ,80个妊娠周期的临床资料进行回顾性分析。结果  80个周期中 ,宫内妊娠率 96 2 5 % (77/ 80 ) ,其中自然流产率 2 3 75 % (1 9/ 80 ) ;妊娠 <1 6周流产率 1 6 2 5 % (1 3/ 80 ) ;妊娠 >1 6周流产率 7 5 0 % (6 / 80 ) ,其中 5周期均发生双胎妊娠 ;分娩率 72 5 0 % (5 8/ 80 ) ,早产率 1 5 0 0 % (1 2 / 80 ) ,宫外孕发生率 3 75 % (3/ 80 )。新生儿死亡率 3 6 1 % (3/ 83) ,均死于三胎妊娠早产。结论 减少IVF -ET后多胎妊娠率 ,加强多胎妊娠的整个孕期监护 ,以利于减少多胎妊娠 >1 6周流产率及早产率 ,是降低IVF -ET后妊娠胎儿丢失的有效方法  相似文献   
37.
Classic therapies are usually ineffective in the treatment of patients with very poor sperm density. The aim of this study was to determine the effect of acupuncture on these males. Semen samples of 20 patients with a history of azoospermia were examined by light microscope (LM) and scanning electron microscope (SEM), with which a microsearch for spermatozoa was carried out. These examinations were performed before and 1 month after acupuncture treatment and revealed that the study group originally contained three severely oligoteratoasthenozoospermic (OTA), two pseudoazoospermic and 15 azoospermic patients. The control group was comprised of 20 untreated males who underwent two semen examinations within a period of 2-4 months and had initial andrological profiles similar to those of the experimental group. No changes in any of the parameters examined were observed in the control group. There was a marked but not significant improvement in the sperm counts of severely OTA males following acupuncture treatment (average = 0.7 +/- 1.1 x 10(6) spermatozoa per ejaculate before treatment vs. 4.3 +/- 3.2 x 10(6) spermatozoa per ejaculate after treatment). A definite increase in sperm count was detected in the ejaculates of 10 (67%) of the 15 azoospermic patients. Seven of these males exhibited post-treatment spermatozoa that were detected even by LM. The sperm production of these seven males increased significantly, from 0 to an average of 1.5 +/- 2.4 x 10(6) spermatozoa per ejaculate (Z = -2.8, P < or = 0.01). Males with genital tract inflammation exhibited the most remarkable improvement in sperm density (on average from 0.3 +/- 0.6 x 10(6) spermatozoa per ejaculate to 3.3 +/- 3.2 x 10(6) spermatozoa per ejaculate; Z = -2.4, P < or = 0.02). Two pregnancies were achieved by the IVF-ICSI procedure. It is concluded that acupuncture may be a useful, nontraumatic treatment for males with very poor sperm density, especially those with a history of genital tract inflammation.  相似文献   
38.
Objective: At present, only limited data are available on endometrial volume during the menstrual cycle. Most of these studies deal with animal models and use magnetic resonance imaging for volume measuring. The application of three-dimensional ultrasound in endometrial volume estimation is the subject of this study.Setting: Patients visiting the outpatient unit of the division of endocrinology and reproductive medicine of a university hospital.Patient(s): Twenty patients with a history of a normal menstrual cycle were selected.Intervention(s): Ultrasound examinations were performed during a single menstrual cycle in addition to routine laboratory tests.Main Outcome Measure(s): Uterus-endometrial volume ratio.Result(s): Data from 18 patients could be evaluated. In 81 examinations the endometrium volume could be determined. Mean endometrial volume measured by three-dimensional ultrasound was 1.23 cm'. Mean uterus volume was 48.93 cm3. The change of the uterus-endometrial volume ratio showed a good correlation with the day of menstrual cycle. Quadratic regression analysis of volume and cycle length was R2 = 0.432.Conclusion(s): Three-dimensional ultrasound allows assessment of volume data of the female internal genitalia. In this study changes of the endometrial volume in menstrual cycles were measured. Additional studies are required to give information on the clinical impact of this new technique of endometrial volume estimation.  相似文献   
39.
综考历代相关文献,虚劳之先天成因有以下几个方面:一是早婚早育,肌体稚弱,精气未生,血气未充,肾元亏虚;二是久病、劳逸过度、性生活失调导致父母体质虚弱;三是高龄生育;四是妊娠失养导致子代先天禀赋薄弱,胎儿气血供养不足,出生后体质虚弱,生长发育受到影响,从而形成虚劳的病理基础。  相似文献   
40.
Previously our work on the haloacid by-products of drinking water disinfection focused on adult exposures. Herein we evaluate the consequence of continuous exposure to dibromoacetic acid (DBA) via drinking water through reproductive development into adulthood. An initial study in which offspring were exposed from gestation day (GD) 15 through adulthood revealed significant delays in preputial separation and vaginal opening, dose-related decreases in the fertility of cauda epididymal sperm, and dose-related diminutions in the sperm membrane protein SP22. Subsequent studies consisted of groups in which exposure ceased on postnatal day 21 (PND 21) versus adulthood. For each exposure, animals were evaluated after puberty (PND 56) as well as at adulthood (PND 120). Exposure to 4, 40, or 400 ppm DBA from GD 15 through PND 21 failed to result in any significant reproductive alterations. By contrast, continuous exposure until adulthood resulted in dose-related alterations consistent with those observed in the dose-finding study. Preputial separation and vaginal opening were delayed 4 and 3 days in males and females exposed to 400 ppm (76.3 mg/kg) DBA. This was associated with increased responsiveness of both the testis and ovary to hCG ex vivo; hCG-stimulated testosterone production by testicular parenchyma on PND 56 was increased at 4 ppm (0.6 mg/kg) DBA and higher. Finally, the quality of proximal cauda epididymal sperm was compromised by continuous exposure to DBA. The sperm membrane proteome was altered in a dose-related manner with SP22, and one of its charged variants, diminished at 40 ppm (3.6 mg/kg) DBA and higher. As more sensitive endpoints are evaluated, lower effect levels can be attributed to haloacid exposure. We are now extending our evaluations to epidemiology studies designed to evaluate sperm quality in men exposed to varying levels of disinfection by-products.  相似文献   
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