This study was undertaken to establish a noninvasive prenatal genetic diagnostic method for trisomy 21 using the fetal nRBCs that is rarely present in maternal circulation. Peripheral venous blood samples were collected from 30 women with an advanced maternal age, abnormal triple marker test results, or abnormal ultrasound findings such as an increased nuchal translucency. The blood samples were treated with heparin. The triple density gradient centrifugation, and MACS using CD45 and CD71 were used to isolate the fetal cells. FISH analysis using probe 21 was performed with GPA-immunostaining. The study population consisted of 30 patients from 13 to 25 weeks of gestation, and nRBCs were separated in all cases. In GPA-immuno FISH analysis using probe 21, 3 cases of trisomy 21 were diagnosed and these results were confirmed by the amniocentesis. In conclusion, a prenatal diagnosis of trisomy 21 through GPA- immuno fluorescence in situ hybridization (FISH) analysis using separated fetal nRBCs is a useful, innovative, accurate, rapid and non-invasive diagnostic method.
Adolescent ; Adult ; Down Syndrome/*diagnosis ; Female ; Human ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Pregnancy/*blood ; Prenatal Diagnosis/*methods

Chorionic Gonadotropin, beta Subunit, Human ; blood ; Down Syndrome ; blood ; diagnosis ; Female ; Humans ; Pregnancy ; Pregnancy, Twin ; Prenatal Diagnosis ; alpha-Fetoproteins ; metabolism

OBJECTIVETo investigate the value of a disintegrin and metalloproteinase 12 secreting form (ADAM12-S) as a maternal serum marker in second trimester screening for trisomy 21 (Down syndrome, DS), and to develop an appropriate prenatal DS screening protocol.

METHODSSerum samples were collected from 53 pregnant women carrying a trisomy 21 fetus and 621 pregnant women with matched gestational age and weight carrying a healthy fetus. ADAM12-S concentrations were determined with a time-resolved fluorescence immunoassay (TRFIA). Curve fitting by weighted regression and other statistical methods were conducted, and the model was optimized for prenatal trisomy 21 screening program in second trimester. ADAM12-S alone or in combination with other two- or three-combination test was selected as a serum marker for prenatal second-trimester screening of trisomy 21 by calculation of detection rate (DR) and false positive rate (FPR).

RESULTSBy comparison, the median multiple of the median (MoM) value of ADAM12-S in DS pregnancy group was higher than that of the control group (P< 0.01). When FPR = 5%, the DR of ADAM12-S was 28.3%, and the positive and negative likelihood ratios were 5.66 and 0.75, respectively. The DR of three-combination test of ADAM12-S, alpha-fetoprotein (AFP) and free beta subunit of human chorionic gonadotropin (β-HCG) has increased to 52.80% from 39.62% of the conventional two-combination test (AFP and free β-HCG). For women with a risk between 1/300 and 1/1000 by two-combination test for DS, the DR has increased from 39.62% to 47.12%, but FPR only increased by 0.8% after adding ADAM12-S as a maternal serum marker.

CONCLUSIONConsidering the increased DR of pregnancies with a risk between 1/300 and 1/1000 in second trimester, ADAM12-S may provide a feasible maternal serum maker when combined with AFP and free β-HCG. The cost-effectiveness ratio is reasonable.

ADAM Proteins ; blood ; ADAM12 Protein ; Biomarkers ; blood ; Disintegrins ; blood ; Down Syndrome ; blood ; diagnosis ; enzymology ; Female ; Humans ; Membrane Proteins ; blood ; Pregnancy ; Pregnancy Trimester, Second ; Prenatal Diagnosis ; methods

The routine prenatal maternal serum testing is widely used for screening of birth defects, including Down syndrome, trisomy 18 syndrome and neural tube defects. The testing results are also associated with other adverse pregnant outcomes such as fetal surface structural abnormalities, gestational hypertension disease, intrahepatic cholestasis of pregnancy, premature rupture of membranes, abortion, stillbirth, intrauterine growth restriction and macrosomia; therefore the abnormal levels of serum markers might be used for predicting these adverse pregnant outcomes.
Biomarkers ; blood ; Chromosomes, Human, Pair 18 ; Down Syndrome ; Female ; Humans ; Neural Tube Defects ; Pregnancy ; Pregnancy Outcome ; Prenatal Diagnosis ; Trisomy

We report a case of transient abnormal myelopoiesis in a Down syndrome fetus diagnosed at 28(+3) weeks of gestation that rapidly progressed to intrauterine death 10 days later. Fetal hepatosplenomegaly with cerebral ventriculomegaly, although not specific, may be a suggestive finding of Down syndrome with transient abnormal myelopoiesis. Prompt fetal blood sampling for liver function test and chromosomal analysis are mandatory for early detection and management.
Adult ; Down Syndrome/*ultrasonography ; Female ; Fetal Blood/cytology ; Fetal Death ; Fetal Diseases/*diagnosis ; Hepatomegaly/ultrasonography ; Humans ; Leukocytosis/diagnosis ; *Myelopoiesis ; Pregnancy ; *Prenatal Diagnosis ; Splenomegaly/ultrasonography ; Thrombocytopenia/diagnosis

To investigate the relationship between low unconjugated estriol (uE3) levels in the second trimester and adverse perinatal outcomes in pregnancies without increased risk for Down's syndrome, 1,096 women under 35 years of age underwent a mid-trimester AFP-hCG-uE3 screening test between January 1995 and June 1998. Multiple pregnancies, maternal diabetes, smoking and elevation of AFP and hCG levels more than 2.0 multiple of median (MoM) were excluded from our study population. The results were divided into a low-uE3 group with uE3 levels at or below 0.75 MoM and a normal uE3 group with uE3 levels above 0.75 MoM. The risk for adverse pregnancy outcome was compared between the two groups and the role of low uE3 as a predictor of adverse pregnancy outcome was determined. The data were assessed using chi 2 or Fisher exact test and then logistic regression was used for the final analysis. The odds ratio (OR) and corresponding 95% confidence intervals (CI) were also calculated. Unconjugated E3 levels at or below 0.75 MoM was significantly associated with fetal growth restriction after adjustment for maternal age, weight, sampling weeks, AFP and hCG levels (OR 0.413, 95% CI 0.174-0.900; P = 0.035). Low uE3 levels in the second-trimester could help in the detection of fetal growth restriction by a low risk group in Down's syndrome. Careful gestational dating and serial clinical and sonographic assessment of fetal growth may be required for the clinician to manage these parturients.
Adult ; Down Syndrome/diagnosis ; Estriol/blood* ; Female ; Fetal Growth Retardation/diagnosis* ; Gonadotropins, Chorionic/blood ; Human ; Pregnancy ; Pregnancy Trimester, Second ; Risk ; alpha-Fetoproteins/analysis

OBJECTIVETo screen and diagnose Down's syndrome during mid-term pregnancy to reduce the number of babies with Down's syndrome.

METHODSWith the multi-level of stratified cluster sampling, twenty thousand and eight hundred and three women at 15-20 weeks gestation were screened by maternal serum AFP and beta-hCG using the time resolved fluoroimmunoassay (TRFIA). Then the screened high-risk women were diagnosed by amniocentesis, cell culture and chromosome analyses. The born children were diagnosed by follow-up and peripheral blood chromosome analyses.

RESULTSSix fetuses were diagnosed by serum screening and amniotic fluid chromosome analyses, and 3 born children were diagnosed by follow-up and peripheral blood chromosome analyses. Nine cases of Down's syndrome were detected in total, with the positive prenatal screen rate being 67% (6/9).

CONCLUSIONThe prenatal screening and diagnosis can reduce the birth of Down's syndrome patients and improve the population quality. However, the diagnosis accuracy still needs to be improved to further reduce the false negative rate and prevent misdiagnosis.

Adult ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Chromosome Aberrations ; Down Syndrome ; blood ; diagnosis ; genetics ; metabolism ; Female ; Fluoroimmunoassay ; Humans ; Pregnancy ; Prenatal Diagnosis ; methods ; Young Adult ; alpha-Fetoproteins ; metabolism

INTRODUCTION: The traditional cytogenetic analysis requires relatively long cell culture time, intensive labour and trained personnel. But, in clinical situations, rapid diagnosis of genetic disease is very important for urgent decision for future management. So we need more rapid and precise diagnostic tools for clinical genetic counselling. The fluorescence in situ hybridization (FISH) has been studied for detecting chromosomal aneuploidies because this method can get rapid and precise results of cytogenetic studies. OBJECTIVE: To evaluate the clinical utility of fluorescence in situ hybridization technique as a diagnostic tool of chromosomal anomaly. METHODS: Peripheral blood or gonadal tissue were obtained from the patients (n=63) clinically suspicious of genetic disease. Chorionic villi (n=6), amniotic fluid (n=9), and fetal cord blood (n=2) were obtained from 15 pregnancies undergoing fetal karyotyping at 9 to 30 weeks of gestation for prenatal genetic counselling. Karyotyping was performed by both traditional cytogenetics and FISH, using commercially available kits. After the procedures, the results of FISH were compared with the results of traditional cytogenetic studies. RESULTS: In a blind series of 17 samples all, including trisomy 21 (1 case), trisomy 18 (1 case), monosomyX (1 case), 47,XYY (1 case), and 47,XXY (1 case), were correctly identified. FISH results were correspondent with conventional karyotyping results in 7 patients with intersex except one case of suspicious of mosaicism. In nine children of Turner syndrome, the results of two methods were correspondent too. There was a fluorescent signal defect in band 15 q11-q13 in one of chromosome 15 in 18 children of 29 patients, clinically suspicious of Prader-Willi syndrome, with FISH method and only four patients were diagnosed as Prader-Willi syndrome with G-banding microscope. It was impossible to identify the defect in chromosome 15 q11-q13 in 10 (34%) children by both methods. Two children of 11 patients, clinically suspicious of Angelman syndrome, were diagnosed as Angelman syndrome with both method respectively. And four children were diagnosed as Angelman syndrome only with FISH method. In 5 cases, we cannot detect the defect in chromosome 15 q11-q13 with both methods. In four cases of Williams syndrome, the results of both methods were as follows; 1 case (25%): diagnosed as Williams syndrome by both methods; 2 cases (50%): diagnosed
Amniotic Fluid ; Aneuploidy ; Angelman Syndrome ; Cell Culture Techniques ; Child ; Chorionic Villi ; Chromosomes, Human, Pair 15 ; Cytogenetic Analysis ; Cytogenetics ; Diagnosis* ; Down Syndrome ; Female ; Fetal Blood ; Fluorescence* ; Gonads ; Humans ; In Situ Hybridization* ; Karyotyping ; Mosaicism ; Prader-Willi Syndrome ; Pregnancy ; Trisomy ; Turner Syndrome ; Williams Syndrome

OBJECTIVETo explore the clinical value of screening the serum markers during the second trimester of pregnancy in preventing congenital birth defect and predicting the pregnancy outcome.

METHODSBetween November, 2011 and October, 2013, a total of 25 520 pregnant women (15-20+6 gestational weeks) underwent a screening test of triple serum markers including free beta-human chorionic gonadotrophin (free βhCG), alpha-fetoprotein (AFP), and unconjugated estriol (µE3) during the second semester of pregnancy. The women identified by the screening test as having high risks were referred to invasive prenatal diagnosis by amniocentesis, or to color Doppler ultrasound examination for suspected patent neural tube defect (NTD), and their pregnancy outcomes were followed up.

RESULTSHigh-risk pregnancies were identified by the screening test in 4.91% (1254/25520) of the total cohort. Of the 818 patients receiving invasive prenatal diagnosis, the abnormal rate was 5.75% (47/818). The high-risk pregnancies identified by the screening test was associated with a significantly higher rate of abnormal outcomes compared with the low-risk pregnancies (1.91% vs 0.1%, P<0.01). Of the 210 high-risk cases of NTD, a definite diagnosis was established in 34 cases. We also found that pregnancies at an advanced age (>35 years) was associated with increased risks for trisomy 21 compared with those at younger ages (15% vs 1.65%P<0.01). The detection rate of abnormal karyotypes in pregnancies with an abnormal MoM value of a single marker was 3.17% (6/189).

CONCLUSIONScreening tests of serum markers during the second trimester of pregnancy can be helpful to identify fetal chromosomal and anatomical anomalies, predict unfavorable pregnancy outcomes, and prevent birth defects in pregnancies at an advanced age. The MoM value of a single marker in the second trimester can be indicative of potential chromosomal abnormalities.

Biomarkers ; blood ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Chromosome Aberrations ; Down Syndrome ; diagnosis ; Estriol ; blood ; Female ; Humans ; Neural Tube Defects ; diagnosis ; Pregnancy ; Pregnancy Outcome ; Pregnancy Trimester, Second ; blood ; Prenatal Diagnosis ; alpha-Fetoproteins ; analysis

OBJECTIVETo investigate the optimal method of screening for Down's syndrome (DS) with maternal serum mankers.

METHODSScreening by maternal serum markers for Down's syndrome was offered to all 2886 pregnant women in Peking Union Medical Hospital during 1996.11-2001.3. Alpha-fetoprotein (AFP), human chorionic gonadotrophin (free beta-HCG) were used as markers during the first year of pregnancy. Alpha-fetoprotein, free human chorionic gonadotrophin (HCG) and pregnancy-associated plasma protein A (PAPP-A) were used as mid pregnancy and first-trimester markers in next three years. Amniocentesis and (CVS) were done in those defined as risk cases.

RESULTSThe detection rate of Down's syndrome by maternal serum markers was 3.8% (11/2886). The proportion of false positive results in group of triple markers (alpha FP, free beta-HCG, PAPP-A) was 5%.

CONCLUSIONSThe PAPP-A was a good marker to detect Down's syndrome in early pregnancy and may be used to predict the outcome during mid trimester of pregnancy. The AFP and free beta-HCG can be useful markers to detect Down's syndrome and fetal abnormality. While prenatal diagnostics can be shifted to an early pregnant period.

Adult ; Amniocentesis ; Biomarkers ; blood ; Chorionic Gonadotropin, beta Subunit, Human ; blood ; Down Syndrome ; diagnosis ; prevention & control ; Female ; Fetal Diseases ; diagnosis ; prevention & control ; Humans ; Mass Screening ; Pregnancy ; blood ; Pregnancy-Associated Plasma Protein-A ; analysis ; Prenatal Diagnosis ; methods ; alpha-Fetoproteins ; analysis