Maternal Serum Levels (maternal + serum_level)

Distribution by Scientific Domains

Selected Abstracts

Maternal serum levels of dimeric inhibin A in pregnancies affected by trisomy 21 in the first trimester

Kevin Spencer
Abstract Dimeric inhibin A was measured in maternal serum samples from 45 pregnancies affected by trisomy 21 and 493 samples from unaffected pregnancies at 10,14 weeks of gestation. Inhibin A levels in affected pregnancies were compared with levels of free ,-hCG and PAPP-A in the same series. In the trisomy 21 group, the median multiple of the median (MoM) inhibin A was not significantly elevated (1.28 vs 1.00) with only 15.5% being above the 95th centile. In contrast, the median MoM free ,-hCG was significantly increased (2.05 vs 1.00) with 36% above the 95th centile and PAPP-A was significantly reduced (0.49 vs 1.00) with 42% below the 5th centile. Inhibin A levels in the trisomy 21 group were significantly correlated with gestational age such that median levels rose from 1.04 at 11 weeks to 1.30 at 12 weeks and 1.67 at 13 weeks. These findings suggest that first trimester biochemical screening for trisomy 21, which is currently optimised using maternal serum free ,-hCG and PAPP-A and fetal nuchal translucency, will not benefit from the inclusion of inhibin A. Copyright 2001 John Wiley & Sons, Ltd. [source]

Risk prediction for Down's syndrome in young pregnant women using maternal serum biomarkers: determination of cut-off risk from receiver operating characteristic curve analysis

Hsiao-Lin Hwa MD PhD
Abstract Objective, The aim of this study was to establish a predictive model for Down's syndrome using maternal age as well as maternal serum levels of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG), and to identify an optimal cut-off risk in women under the age of 35 years to improve sensitivity. Methods, Logistic regression models were utilized to predict fetal Down's syndrome as a function of maternal age and logarithm of levels of AFP as well as hCG using training data of 20 pregnancies with fetal Down's syndrome and 9730 unaffected pregnancies. Validation was performed using data of another nine affected pregnancies and 3496 unaffected pregnancies. Receiver operating characteristic (ROC) curves were plotted. Results, Based on the newly established logistic regression equations, the optimal cut-off risk from the ROC curve analysis was at 1:499, with a 17.8% false-positive rate and a 90.0% sensitivity. A suboptimal cut-off risk was estimated at 1:332, with a 12.0% false-positive rate and an 80% sensitivity. Conclusion, A predictive model for Down's syndrome was developed using logistic regression. By ROC curve analysis and clinical consideration, the cut-off risk for young pregnant women could be determined. [source]

Detection of maternal serum hCG glycoform variants in the second trimester of pregnancies affected by Down syndrome using a lectin immunoassay

J. A. Talbot
Abstract Aim To assess whether glycoform variants of human chorionic gonadotrophin (hCG) are present in altered concentrations in the maternal serum in pregnancies affected by Down syndrome. Methods In a series of 50 cases of pregnancies complicated by Down syndrome and 278 unaffected pregnancies, we have examined maternal serum levels of hCG glycoforms (GlyhCG) in samples collected in the second trimester (14 to 21 weeks) using a sialic acid binding lectin immunoassay. We have compared these levels with those of other second trimester serum markers (Free ,-hCG, alpha fetaprotein (AFP) and Total hCG) and modelled detection rates and false positive rates of various biochemical markers in conjunction with maternal age using a maternal age standardized population. Results Maternal serum GlyhCG in cases of Down syndrome was significantly elevated (Median MoM 1.81) with 15 of 50 (30%) cases above the 95th centile for unaffected pregnancies. Free ,-hCG was also elevated (Median MoM 2.16) with 18 of 50 (36%) cases above the 95th centile. AFP levels were reduced (Median MoM 0.75) with 9 of 50 (18%) cases below the 5th centile. Total hCG levels whilst elevated (Median MoM 1.88) had only 15 of 50 (30%) cases above the 95th centile. Maternal serum GlyhCG levels showed significant correlation with total hCG and free ,-hCG (r = 0.6880 and 0.6922) in the Down group but not with AFP (r = 0.1237). When GlyhCG was combined together with AFP and maternal age, at a 5% false positive rate, the modelled detection rate was 53%, some 13% lower than when free ,-hCG was used and some 7% lower than when total hCG was used. Conclusion Maternal serum GlyhCG, as measured by the sialic acid,binding lectin immunoassay is unlikely to be of additional value when screening for Down syndrome in the second trimester. Copyright 2002 John Wiley & Sons, Ltd. [source]

Reduced maternal serum concentrations of angiopoietin-2 in the first trimester precede intrauterine growth restriction associated with placental insufficiency

Y Wang
The aim of this study was to investigate whether maternal serum levels of angiopoietin-2 (Ang-2) and pregnancy-associated plasma protein A (PAPP-A) are associated with subsequent intrauterine growth restriction (IUGR). Ang-2 was measured in 29 nonpregnant and 44 pregnant women at 10,13 weeks of gestation. The median concentration of Ang-2 was 26.61 ng/ml in normal pregnant women compared with 1.71 ng/ml in nonpregnant controls (P < 0.01). Women who subsequently developed severe IUGR had lower levels of Ang-2 compared with normal pregnant controls (P < 0.01). PAPP-A levels were similar in all pregnant groups. These findings suggest that Ang-2 should be evaluated for its ability to predict pregnancies that later are affected by IUGR. [source]