BACKGROUND Early placental and embryo development occur in a physiologically low oxygen environment, with a rise in oxygen tension within the placenta towards the end of the first trimester. Oxygen is implicated in the regulation of trophoblast differentiation and invasion. This study examined the effects of oxygen tension on extravillous trophoblast outgrowth and migration from normal pregnanc...

OBJECTIVES To derive models for estimating risk of miscarriage and stillbirth from maternal characteristics and findings of first-trimester screening for aneuploidies and to define the procedure-related risk of chorionic villus sampling (CVS) after adjusting for these factors. METHOD We examined 33 856 singleton pregnancies at 11(+0) to 13(+6) weeks, and in 2396 CVS was carried out. Logistic ...

OBJECTIVE The technique used to perform transabdominal chorionic villus sampling (CVS) is not standardized, but aspiration of villi is generally obtained by discontinuous vacuum created in a syringe, manually or by a hand-grip device. We evaluated the feasibility of a new method of performing CVS which employs a 4-mL Vacutainer connected to the needle, producing a continuous negative pressure. ...

OBJECTIVE To assess the fetal loss rate following amniocentesis and chorionic villus sampling (CVS). METHODS This was a national registry-based cohort study, including all singleton pregnant women who had an amniocentesis (n = 32 852) or CVS (n = 31 355) in Denmark between 1996 and 2006. Personal registration numbers of women having had an amniocentesis or a CVS were retrieved from the Danish...

OBJECTIVE The purpose of this study was to demonstrate that digital polymerase chain reaction (PCR) enables rapid, allele independent molecular detection of fetal aneuploidy. STUDY DESIGN Twenty-four amniocentesis and 16 chorionic villus samples were used for microfluidic digital PCR analysis. Three thousand and sixty PCR reactions were performed for each of the target chromosomes (X, Y, 13, ...

Fragile X syndrome, one of the most common human genetic diseases, is characterised by a unique genetic mechanism which involves dynamic mutation because of a heritable unstable DNA sequence and abnormal DNA methylation. Direct detection of the dynamic mutation and its methylation status at the DNA level would facilitate reliable tests for prenatal and postnatal diagnosis of the disease and for...

OBJECTIVE To assess the accuracy of fetal sex determination at 11-14 weeks of gestation. METHODS Fetal gender assessment by ultrasound was prospectively carried out in 172 singleton pregnancies at 11-14 weeks of gestation immediately before chorionic villus sampling for karyotyping. The genital region was examined in a midsagittal plane and the fetal gender was assigned as male if the angle o...

A register of families with Duchenne muscular dystrophy (DMD) in Wales was set up in 1973 and has been regularly maintained ever since. All women at significant risk in these families were offered estimation of their carrier status by creatine kinase and pedigree analysis. A total of 225 of the 512 women tested was assigned a risk of carrying the DMD gene of less than 5%. One hundred and twenty...

Objective: To assess the performance of diverse prenatal diagnostic approaches for nuchal translucency (NT) thickening and to investigate optimal screening or action with a NT 95th percentile-3.50 mm. Methods: A retrospective analysis 2,328 pregnancies ≥ percentile through ultrasound-guided transabdominal chorionic villus sampling (CVS), amniocentesis, cordocentesis obtained clinical samples (c...