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Three cases of hydrops fetalis presented in the second trimester as screen-positive for Down syndrome using multiple maternal serum markers. One case was a karyotypically normal female; one case was a monosomy X (Turner syndrome); and one case was a trisomy 21 (Down syndrome). In each case, the maternal serum human chorionic gonadotrophin (hCG) was disproportionately elevated. These cases support the contention that hydrops fetalis of any aetiology may present as screen-positive when using multiple maternal serum markers for Down syndrome. Further cases will be necessary before it can be determined whether a disproportionately elevated hCG is predictive of hydrops.  相似文献   
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Objective To develop a theoretical framework for analysing ethnic differences in determinants of participation and non-participation in prenatal screening for Down syndrome. Methods We applied Weinstein's Precaution Adoption Process (PAP) Model to the decision of whether or not to participate in prenatal screening for Down syndrome. The prenatal screening stage model was specified by reviewing the empirical literature and by data from seven focus group interviews with Dutch, Turkish and Surinamese pregnant women in the Netherlands. Results We identified 11 empirical studies on ethnic differences in determinants of participation and non-participation in prenatal screening for Down syndrome. The focus group interviews showed that almost all stages and determinants in the stage model were relevant in women's decision-making process. However, there were ethnic variations in the relevance of determinants, such as beliefs about personal consequences of having a child with Down syndrome or cultural and religious norms. Discussion The prenatal screening stage model can be applied as a framework to describe the decision-making process of pregnant women from different ethnic backgrounds. It provides scope for developing culturally sensitive, tailored methods to guide pregnant women towards informed decision-making on participation or non-participation in prenatal screening for Down syndrome. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
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Discordant growth in twins contributes significantly to rates of perinatal morbidity and mortality. These rates vary according to chorionicity, timing of onset and severity. We have reviewed English language literature in Medline since 1980. It is clear that diagnosis of discordant growth has improved due to the use of serial ultrasound examination. Following the detection of differences in fetal size, diagnosis is facilitated by umbilical artery and fetal Doppler studies. Management options vary according to chorionicity, timing of onset and umbilical-fetal Doppler studies. The mode of delivery in discordant twins remains controversial. We conclude that ultrasound surveillance of twin gestations, combining serial biometry and selective Doppler studies, is effective in the recognition of siginificant intrauterine growth restriction in co-twins. Differences in etiology and management underscore the imortance of establishing chorionicity routinely as soon as twin gestation is diagnosed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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