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To explore the prevalence and risk factors of infertility in Iran, a total of 12 285 ever-married women aged 15-50 years old and their husbands (if available) were interviewed by 82 female general practitioners and answered a self-administered questionnaire on several aspects of infertility. They were identified from the national population in 30 counties, and invited to a confidential interview. Data were obtained about their age, education, marital status, toxic habits, medical history, disabilities and illnesses, help-seeking, economy, ethnicity, geographic location, contraceptive use and age at which they had first intercourse. This study used the definition of childlessness proposed by World Health Organization: 'the woman has never conceived despite cohabitation and exposure to pregnancy for a period of 2 years'. The overall prevalence of infertility was 8% (95% CI: 3.2-15.0). The weighted national estimate of primary infertility was 4.6% (95% CI: 3.6-5.2). There was a pronounced regional pattern in the levels of primary infertility. The primary infertility increased significantly from 2.6 to 4.3 to 5.5% for the 1985-1989, 1990-1994 and 1995-2000 marriage cohorts. The prevalence of secondary infertility was 3.4% (95% CI: 2.4-5.1). Overall the prevalence of infertility falls within a relatively wide range being high in the Southern counties, and low in the Northern counties. The probability of first pregnancy at the end of 2 years of marriage was 0.78 for all ever-married women. The prevalence of infertility increased with age (linear chi-square 198.012, 1 d.f., p = 0.01). The age pattern of infertility also varies quite markedly across the counties analysed. No effect of race was detected; neither the intercept (analysis of covariance p = 0.36) nor the slope of the age relationship was influenced by race (analysis of covariance p = 0.41). Infertility were observed as significantly higher in the presence of history of tubo-ovarian surgery [odds ratio (OR): 1.43; 95% CI: 1.28-2.23; p = 0.01], salpingitis (OR: 2.34; 95% CI: 1.31-4.3; p = 0.016), ectopic pregnancy (OR: 2.45; 95% CI: 1.90-3.44; p = 0.04), varicocele (OR: 2.85; 95% CI: 1.61-5.20; p = 0.01) and cryptorchidism (OR: 3.81; 95% CI: 2.51-4.28; p = 0.031). This study provides a quantitative estimate of the prevalence and main risk factors for infertility in Iranian couples. Yet, further studies on the cause of primary and secondary infertility and geographical variations in the incidence and prevalence of infertility in Iran are needed.  相似文献   
96.

Objective

To compare the obstetric and neonatal outcomes of twin pregnancies conceived by assisted reproduction technology (ART) with spontaneously conceived (SC) twin pregnancies.

Study design

A prospective cohort study compared all dichorionic twin pregnancies in nulliparous women following fresh in vitro fertilization/intra-cytoplasmic sperm injection (ICSI) or ICSI cycles at Royan Institute (n = 320) with SC dichorionic twin pregnancies in nulliparous women at Arash Women's hospital (n = 170) from January 2008 to October 2010. These pregnancies were followed-up until hospital discharge following delivery. Obstetric and neonatal outcomes of SC and ART twin pregnancies were compared.

Results

Multivariate analysis, adjusted for maternal age and body mass index, revealed that the obstetric outcomes were similar in both groups. However, the risks of very preterm birth [odds ratio (OR) 5.2, 95% confidence interval (CI) 2.1–12.9], extremely low birth weight (OR 2.2, 95% CI 1.0–3.9), admission to a neonatal intensive care unit (OR 2.0, 95% CI 1.2–3.2) and perinatal mortality (OR 2.3, 95% CI 1.2–4.0) were higher in the ART group.

Conclusions

The maternal outcomes of ART dichorionic twins were comparable with those of SC twins. However, despite the same obstetric management, the rates of very preterm birth, extremely low birth weight, admission to a neonatal intensive care unit and perinatal mortality were significantly higher in the ART group.  相似文献   
97.

Objective

Precocious puberty is of concern because of the underlying disorders, the short adult stature, and the psychosocial difficulties. This study was carried out in order to evaluate the characteristics of children referred to pediatric endocrinology clinic with diagnosis of precocious puberty.

Methods

In a cross-sectional study between February 2007 and September 2009, all of the children referred to pediatric endocrinology clinic in North-West Iran with diagnosis of precocious puberty were recruited.

Findings

Data of 106 girls (82.2%) and 23 boys (17.8%) were analyzed. Mean age of the patients at the time of referral was 6.6±2.8 years (ranging 0.3-14 yr), which was 7±3.9 (ranging 0.3-14 yr) for boys and 6.6±2.5 (ranging 0.8-12 yr) for girls (P=0.6). Out of 129 subjects, 56(43.4%) had precocious puberty, 71.4% (35 cases) of them were due to central precocious puberty and 28.6% (16 cases) were pseudo-precocious puberty. 73 out of 129 subjects (56.6%) were due to normal variants of puberty, normal puberty, and no puberty. 87.5% of subjects with central precocious puberty were idiopathic.

Conclusion

Most of children referred with diagnosis of precocious puberty have benign normal variants. Most of cases with precocious puberty are affected with central precocious puberty, especially with idiopathic form of it.  相似文献   
98.
Previous studies have revealed a novel interaction between deoxyhemoglobin and nitrite to generate nitric oxide (NO) in blood. It has been proposed that nitrite acts as an endocrine reservoir of NO and contributes to hypoxic vasodilation and signaling. Here, we characterize the nitrite reductase activity of deoxymyoglobin, which reduces nitrite approximately 36 times faster than deoxyhemoglobin because of its lower heme redox potential. We hypothesize that physiologically this reaction releases NO in proximity to mitochondria and regulates respiration through cytochrome c oxidase. Spectrophotometric and chemiluminescent measurements show that the deoxymyoglobin-nitrite reaction produces NO in a second order reaction that is dependent on deoxymyoglobin, nitrite and proton concentration, with a bimolecular rate constant of 12.4 mol/L(-1)s(-1) (pH 7.4, 37 degrees C). Because the IC(50) for NO-dependent inhibition of mitochondrial respiration is approximately 100 nmol/L at physiological oxygen tensions (5 to 10 mumol/L); we tested whether the myoglobin-dependent reduction of nitrite could inhibit respiration. Indeed, the addition of deoxymyoglobin and nitrite to isolated rat heart and liver mitochondria resulted in the inhibition of respiration, while myoglobin or nitrite alone had no effect. The addition of nitrite to rat heart homogenate containing both myoglobin and mitochondria resulted in NO generation and inhibition of respiration; these effects were blocked by myoglobin oxidation with ferricyanide but not by the xanthine oxidoreductase inhibitor allopurinol. These data expand on the paradigm that heme-globins conserve and generate NO via nitrite reduction along physiological oxygen gradients, and further demonstrate that NO generation from nitrite reduction can escape heme autocapture to regulate NO-dependent signaling.  相似文献   
99.
Objectives: The proportion of the population aged 65 years and over in Australia is expected to increase substantially, and more people in this age group are retaining their teeth and will require dental care. The objective of this study was to assess the oral health status of inpatients over the age of 65. Methods: Dental examinations were performed on inpatients at Fremantle Hospital. Standardised assessment forms were used to investigate factors related to medical history, hospital admission and oral health needs. Results: A total of 104 persons were examined, 56% were dentate. The dentate participants had an average decayed, missing and filled (DMF)‐index of 21.6 (SD 7.1). All edentulous participants had dentures and the estimated average age of their dentures was 18.1 years. Although the majority of participants (70.2%) were satisfied with their oral health status, 76.6% were professionally assessed to be in need of immediate dental care. Among the edentulous participants, 47.1% needed new dentures. Among all the participants, 75.3% also needed improved oral hygiene. Conclusion: There is a need to fully assess availability, appropriateness and effectiveness of models of oral health care delivery among the older population. This study clearly indicates a current problem and high levels of unmet need. With an increasing ageing population and higher retention levels of natural dentitions, this will result in higher levels of oral disease and need for prevention and care.  相似文献   
100.
BACKGROUND: Depth of invasion beyond the muscularis propria (MP) by T3 rectal cancer can vary. The purpose of the present paper was to determine if depth of invasion beyond MP, as assessed by preoperative endoscopic ultrasound (EUS), can predict tumor recurrence in patients with T3 rectal tumors. METHODS: Patients with T3NxM0 rectal cancer, as determined by EUS, who underwent surgical resection (without preoperative neoadjuvant therapy) were reviewed by two blinded endosonographers. Tumors were classified as minimally invasive T3 (invasion 2 mm). RESULTS: Forty-two patients with T3 rectal tumors underwent surgical resection without receiving preoperative neoadjuvant therapy, of whom 14 had minimally invasive T3 and 28 had advanced T3 disease, as determined by preoperative EUS. Median follow up was 19 months. Tumor recurrence rates in minimally invasive and advanced T3 tumors were 14.3% and 39.3%, respectively, P = 0.02 (log-rank test). Adjusting for nodal status and postoperative adjuvant therapy administration, Cox proportional hazards model demonstrated advanced T3 disease (by EUS) to predict tumor recurrence, hazard ratio, 2.28 (95% confidence interval: 1.17-5.81), P = 0.01. CONCLUSIONS: All T3 rectal tumors are not equal, with minimally invasive disease carrying a more favorable prognosis. By discriminating minimally invasive from advanced T3 disease, preoperative EUS provides important prognostic information. Further subclassification of T3 tumors, based on preoperative EUS staging, should be considered to enhance selection of patients for neoadjuvant therapy.  相似文献   
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