孕中期妇女血清AFP、F-β hCG测定筛查唐氏综合征

目的探讨检测孕中期妇女(14～20w)外周血清中甲胎蛋白(AFP)的游离绒毛膜促性腺激素(F-βhCG)的含量对于筛查唐氏综合征患儿的有效性.方法应用磁性分离酶免疫测定技术测定血清中AP、F-βhCG的含量,结合孕妇临床资料用分析软件进行分析,并通过羊水细胞染色体核型分析给予确诊.结果在接受血清筛查的2849例孕妇中,筛出唐氏综合征高危312例,筛查阳性率为10.95%,其中有174例接受羊水染色体检查,发现2例唐氏综合征患儿.筛出神经管缺损高危61例,全部做了B超检查,发现2例神经管缺损患儿.结论测定孕中期妇女血清AFP、F-βhCG的含量并进行风险分析,对筛查唐氏综合征患儿,降低其出生机率具有重要意义.     

金华地区孕中期唐氏综合征产前筛查三联筛查的应用

目的探讨孕中期血清三标记物用于唐氏综合征筛查对胎儿染色体异常检出的实用价值。方法采用时间分辨荧光免疫技术,对2011年1月到2011年6月金华地区的11 604例孕15～20周,预产年龄〈35周岁的孕妇进行血清生化标志物甲胎蛋白（AFP）、游离β绒毛膜促性腺激素（F-βHCG）及游离雌三醇（uE3）浓度检测,结合孕妇年龄、体重、孕周等因素,利用配套软件计算胎儿患唐氏综合征的风险,并对筛查出的高风险孕妇进行羊水染色体检查,所有孕妇都随访到分娩后。结果筛查的11 604例孕妇中,高风险574例,筛查阳性率为4.95%,确诊21三体5例,18三体2例,NTD 1例,确诊率1.39%。筛查阴性的孕妇中检出21三体1例,唐氏综合征的检出率为83.3%（5/6）。结论孕中期唐氏综合征产前筛查三联筛查有提高检出染色体异常胎儿的作用,对减少出生缺陷,提高人口素质有重要意义。     

孕中期母血清标记物筛查唐氏综合征及其它先天畸形的研究

目的进行唐氏综合征及其它先天畸形的产前筛查、诊断,以降低出生缺陷.方法对2812例孕14～20w的孕妇采用酶联免疫方法检测孕妇血清AFP和β-HCG浓度,通过"优生胜算"软件计算危险系数,对唐氏高危孕妇取羊水作染色体和基因诊断;对神经管缺损高危孕妇行B超检查.结果在2812例孕妇中筛查出唐氏综合征、神经管缺、及18、13三体高危315例,占筛查总数的11.2%;有121人愿意进一步确诊,发现2例异常妊娠; 27例18、13三体高危孕妇,虽未作进一步确诊,但有2例已胎死宫内,证明也为异常妊娠;在神经管缺损高危的79例中,全部作了B超检查,发现1例神经管缺损患儿.结论母血清标记物进行唐氏综合征及其它先天畸形的产前筛查并结合其它方法进行诊断,对降低出生缺陷具有积极意义.     

11400例孕中期孕妇唐氏综合征的血清筛查和产前诊断分析

目的 检测妊娠中期孕妇血清甲胎蛋白(AFP)、游离-B-绒毛膜促性腺激素(Free-β-HCG),进行孕中期胎儿唐氏综合征的无创性筛查.方法 对11400名15～20周孕妇采用时间分辨免疫荧光分析法检测孕妇血中AFP和β-HCG浓度,结合孕妇年龄、体重、孕周等因素计算风险率.对唐氏综合征高危的孕妇进行羊水细胞染色体分析,神经管缺损(NTD)高危者行超声波检查.结果 在11400名孕妇中21-三体高危791例,占筛查总数的6.94%;18-三体高危315例,占筛查总数的2.76%;神经管缺损高危54例,占筛查总数的0.47%;在769例羊水细胞染色体检查中,共检测出?鲻 异常核型23例.结论 产前筛查、产前诊断对减少出生缺陷的发生,具有重要意义.     

唐氏综合征孕中期产前筛查与产前诊断结果分析

目的检测孕妇血清甲胎蛋白（AFP）,游离-β-绒毛膜促性腺激素（Free-β-HCG）,进行孕中期胎儿唐氏综合征的无创伤性筛查。方法采用金标定量系统对孕中期（14-22w）妇女进行AFP、Free-β-HCG检测,结合母龄、孕周、体重等因素,经专用软件进行分析校正,计算风险率,对高风险孕妇在知情的情况下,自愿选择羊膜腔穿刺,进行羊水细胞染色体核型分析。结果接受筛查的1568名孕妇中筛查出唐氏综合征高风险104例,占筛查总数的6.63%。其中62例接受羊水细胞染色体检查,占高危孕妇的59.62%。检出染色体异常核型14例,占高危孕妇接受羊水细胞培养染色体检查的22.58%。结论利用孕妇血清AFP、Free-β-HCG进行孕中期胎儿无创伤性产前筛查,结合产前诊断,对减少出生缺陷儿的出生,具有重要意义。     

唐氏综合征孕中期产前筛查及产前诊断的临床价值

目的探讨唐氏综合征的产前筛查和产前诊断在预防出生缺陷中的价值。方法对68813例孕15-20w的孕妇采用时间分辨荧光免疫方法检测血清AFP和B-HCG浓度,通过Maiticale软件计算危险系数,对唐氏高危和18-三体高危孕妇取羊水获脐血作染色体诊断,对神经管缺陷（NTD）高危孕妇行系统超声检查。结果筛查68813例孕妇,其中2632例为唐氏综合征或18-三体综合征高分险病例,占总筛查人数的3.82%;NTD高风险542例,占0.79%。接受羊水或脐血染色体检查1772例（占总阳性数的67.32%）,检出异常核型67例,占异常发生率3.78%;NTD高风险行超声检查证实胎儿畸形58例,占筛查高危孕妇的10.7%。结论孕中期产前筛查结合产前诊断可以有效预防出生缺陷的发生。     

6546例孕中期孕妇唐氏综合征产前筛查临床分析

目的探讨孕中期唐氏综合征血清学检查在预防出生缺陷中的价值。方法对6546例孕14～20w孕妇进行血清学筛查,筛查出唐氏综合征高风险孕妇进行产前诊断,对神经管缺陷（NTD）高危孕妇进行系统超声检查。结果筛查6546例孕妇,筛查出唐氏综合征高风险孕妇210例,高风险率3.21%。NTD高风险45例,占筛查人数的0.68%。接受羊水检查129例（占总阳性数的61.4%）,检出异常核型4例,占异常发生率3.1%。假阴性1例,占0.02%。NTD高风险行超声检查证实胎儿畸形4例,占筛查高危孕妇的10.1%。结论孕中期母体血清筛查对唐氏综合征的筛查是一种有效的检查项目。     

妊娠中期唐氏综合征筛查及产前诊断应用分析

目的探讨妊娠中期筛查唐氏综合征的临床意义。方法采用酶联免疫吸附法对孕14-20周的孕妇进行血清绒毛膜促性腺激素和甲胎蛋白检测,对高风险孕妇进行羊膜腔穿刺,羊水细胞染色体核型分析确诊。结果 1146例接受筛查的孕妇,发现唐氏综合征2例。结论孕妇血清绒毛膜促性腺激素和甲胎蛋白两联筛查唐氏综合征在基层是可行的,针对性地开展羊膜腔穿刺,减少21-三体患儿的出生,对提高人口素质有积极意义。     

妊娠中期孕妇唐氏综合征筛查结果分析

目的探讨孕妇血清生化标志物甲胎蛋白(AFP)、绒毛膜促性腺激素(βHCG)和游离雌三醇(uE3)对孕中期孕妇进行唐氏综合征为主的先天缺陷筛查的作用。方法对孕中期(14～20w)妇女进行上述三项血清生化指标检测,经过软件计算风险,对可能影响检测结果的部分因素,如孕妇年龄、体重、孕周等加以分析校正,对高风险孕妇,进一步行羊水或脐血染色体检查及B超进行确诊。结果 1965例孕妇中,发现唐氏综合征2例,神经管缺陷1例。结论孕中期血清AFP、βHCG和uE3三项血清生化指标联合检测,对于严重先天性缺陷儿的宫内诊断具有重要的临床价值,筛查结果高危孕妇应进一步行羊水染色体或B超检查确诊,以减少缺陷儿出生。     

10484例孕中期唐氏综合征筛查结果分析

目的通过对孕妇行孕中期血清生化指标产前筛查,发现孕期胎儿染色体病及神经管发育异常,降低出生缺陷率。方法采用时间分辨免疫荧光法（DELFLA）Eu和Sm双标记试剂盒,测定孕妇空腹静脉血清AFP和Freeβ-HCG浓度,结合孕妇年龄、体重、是否双胎、有无糖尿病史及吸烟史等因素,采用随机软件计算唐氏综合征（DS）和神经管缺陷（NTD）的风险率。在10484例孕中期筛查孕妇中,高风险1146例,筛查阳性率10.93%,DS高风险孕妇1059例。18-三体高风险34例,NTD高风险53例。共做产前诊断506例,包括羊水细胞培养和脐带血细胞培养。诊断率为47.29%。对2007年6月30日以前筛查高风险孕妇进行了产后随访。结果共发现唐氏综合征9例,其中漏诊2例,本室唐氏综合征发病率为0.86‰（9/10484）。其他染色体异常7例,染色体异常总发病率为1.53‰（16/10484）。胎儿畸形、死胎、等其他胎儿发育异常38例。结论孕中期血清筛查对于降低唐氏综合征非常必要,但只有将多种检查和临床表现结合起来分析,才能真正提高产前筛查的效果,降低出生缺陷率。     

AFP and age screening for Down syndrome

The availability of maternal serum alpha-fetoprotein (AFP) values from neural tube defect screening programmes offers the opportunity to improve the effectiveness of screening for Down syndrome. By appropriately combining information on maternal serum AFP and maternal age fewer women would need an amniocentesis to detect a given number of Down syndrome pregnancies or, for a given number of women having amniocentesis, more cases of Down syndrome would be detected than if age alone were used. For example to detect 40% of pregnancies with Down syndrome using AFP and age, 7% of women would need an amniocentesis compared with 11% using age alone. If an amniocentesis and a chromosome analysis together cost $1,000 this is equivalent to a saving of $37,000 per 1000 women screened. The use of AFP as well as age in Down syndrome screening allows patients to be better informed of their risk of having an affected pregnancy. For example, a 35-year-old woman has a risk of a Down syndrome term pregnancy of about 1:380, the risk is 1:120 if the AFP level is 0.40 multiples of the normal median (MoM) and 1:1800 if it is 2.50 MoM. Software providing computer assisted test interpretation has been produced to facilitate the estimation of risk and to identify women with positive screening results.     

唐氏综合征产前筛查与诊断

目的探讨孕中期母血生化标志物在筛查唐氏综合征胎儿中的作用.方法用酶标定量法对孕14～20w的1580例孕妇血清中β-HCG、AFP进行检测,经过风险计算,对高危孕妇进行羊水细胞遗传学检查或/和B超检查.结果1580例孕妇中唐氏(DS)高危孕妇146例,筛出率9.24%;神经管畸形(NTD)高危孕妇42例,筛出率2.66%.在高危孕妇中4例羊水细胞培养胎儿染色体异常,1例B超诊断为胎儿脑积水.结论孕中期母血生化标志物是筛查胎儿染色体异常和神经管畸形的理想指标.     

Preimplantation genetic diagnosis for couples at high risk of Down syndrome pregnancy owing to parental translocation or mosaicism

The population risk for trisomy 21 is 1 in 700 births but some couples are at a much higher risk owing to parental translocation or mosaicism. We report on the first attempt to carry out preimplantation genetic diagnosis for two such couples using cleavage stage embryo biopsy and dual colour FISH analysis. Each couple underwent two treatment cycles. Couple 1 (suspected gonadal mosaicism for trisomy 21) had two embryos normal for chromosome 21 transferred, but no pregnancy resulted; 64% (7/11) unfertilised oocytes/embryos showed chromosome 21 aneuploidy. Couple 2 (46,XX,t(6;21)(q13;q22.3)) had a single embryo transferred resulting in a biochemical pregnancy; 91% (10/11) oocytes/embryos showed chromosome 21 imbalance, most resulting from 3:1 segregation of this translocation at gametogenesis. The opportunity to test embryos before implantation enables the outcome of female meiosis to be studied for the first time and the recurrence risk for a Down syndrome pregnancy to be assessed.


Keywords: preimplantation genetic diagnosis; Down syndrome; reciprocal translocation; gonadal mosaicism     

Differential increases in AFP,hCG, and uE3 in twin pregnancies: Impact on attempts to quantify Down syndrome screening calculations

Since the advent of multiple marker screening (MMS) for Down syndrome (DS) risk calculations, limitations for twins have been apparent. Recent attempts have been made to extrapolate mathematically singleton risks to twins. Here we investigate the pattern of levels among AFP, hCG, and uE3 in twins. MMS screening data from 4,443 twin pregnancies were compared to those from 258,885 singletons from 14–21 weeks of gestational age during a 3-year period (1992–1994) in our laboratory. Medians were determined for singletons and twins, and the ratios of twins to singletons were derived. Median AFP levels for twins are approximately double those of singletons, but median increases for hCG and uE3 are less than double. The data were divided further by ethnic groups (white, African American, Asian, and Hispanic), among which there were significant variations in medians, but not in the ratios of twins to singletons. The increased serum levels of different markers in twins are not consistent across analytes, possibly reflecting independent development of different compartments. Such differences mean that a mere mathematical conversion of singleton DS risks would be imbalanced among the analytes and cannot be applied reasonably to twins. Ethnic-specific databases are as important in twins as they are in singletons. Am. J. Med. Genet. 73:109–112, 1997. © 1997 Wiley-Liss, Inc.     

Parity and Down syndrome

Previous studies have suggested a positive correlation between grand multiparity and the incidence of Down syndrome (DS). In order to study different parities as risk factors for DS, the Swedish health registries were used, and 2,615 infants with Down syndrome were selected from 2,184,590 infants born in 1973–1993. A statistically significant risk decrease for primiparas, and a significant risk increase for grand multiparas (5+), was found (age-adjusted odds ratios: 0.87 (95% CI: 0.80–0.96) and 1.40 (95% CI: 1.18–1.65)), respectively. Potential confounders, such as the effect of truncated maternal 1-year age classes, citizenship, socioeconomic level, etc., were evaluated but were found to have only marginal effects. Evidence suggesting that the extension of prenatal diagnosis during the study period has decreased the incidence of DS among women of parity 1–4, but not among women of parity 5+, was found. The hypothesis that Swedish grand multiparas may have another attitude toward prenatal diagnosis than women of lower parities was confirmed when, in a data set containing information on 872 amniocenteses, a significantly lower rate of grand multiparity than expected was found. For the negative association between primiparity and DS, no obvious confounder was found. Am. J. Med. Genet. 70:196–201, 1997. © 1997 Wiley-Liss, Inc.