Nasal bone in first-trimester screening for trisomy 21.

Objective: This study was undertaken to investigate the impact of incorporating assessment of the nasal bone into first-trimester combined screening by fetal nuchal translucency (NT) thickness and maternal serum biochemistry.

Study Design: In this prospective combined screening study for trisomy 21, the fetal nasal bone was also examined and classified as present or absent. A multivariate approach was used to calculate patient-specific risks for trisomy 21 and the detection rate (DR) and false-positive rate (FPR) were estimated.

Cystic hygromas, nuchal edema, and nuchal translucency at 11-14 weeks of gestation.

Objective: To estimate the incidence of septations in fetuses with increased nuchal translucency (NT) thickness, and to investigate the relationship between the length and thickness of the translucency and whether the length or septations provide useful information concerning the fetal karyotype in addition to that provided by the NT thickness alone.

Methods: We examined 386 fetuses with NT thickness equal to or above the 95th percentile for crown-rump length (CRL). A transverse suboccipitobregmatic section of the fetal head was taken to determine whether the sonolucency was septated, and a midsagittal longitudinal section was used to measure NT thickness, CRL, the longitudinal distance between the occiput and the lower end of the sonolucency toward the fetal sacrum (NT length) and the length between the occiput and the sacral tip (spinal length).

Sonographic screening for trisomy 13 at 11 to 13(+6) weeks of gestation.

Objective: The purpose of this study was to examine the sonographic features of trisomy 13 at 11 to 13(+6) weeks of gestation.

Study Design: This was a retrospective study that examined the features of trisomy 13 at the ultrasound scan at 11 to 13(+6) weeks of gestation, which in our center is performed for the measurement of crown-rump length, nuchal translucency thickness, and fetal heart rate and the examination for major defects.

Results: In the 181 fetuses with trisomy 13, there were holoprosencephaly, exomphalos, and/or megacystis in 92 fetuses (50.

Relation between increased fetal nuchal translucency thickness and chromosomal defects.

Objective: To examine the prevalence and distribution of all chromosomal defects in fetuses with increased nuchal translucency thickness.

Methods: Assessment of risk for trisomy 21 was carried out by a combination of maternal age and fetal nuchal translucency thickness at 11-13 + 6 weeks. A search of the database was made to identify, first, all singleton pregnancies in which fetal karyotyping was carried out and, second, the cases where the fetal nuchal translucency was equal to or above the 95th centile for fetal crown-rump length.

Maternal serum biochemistry at 11-13(+6) weeks in relation to the presence or absence of the fetal nasal bone on ultrasonography in chromosomally abnormal fetuses: an updated analysis of integrated ultrasound and biochemical screening.

Background: Screening for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness and maternal serum free beta-hCG and pregnancy associated plasma protein-A (PAPP-A) at 11-13(+6) weeks of gestation is associated with a detection rate of 90%, for a false-positive rate of 5%. Recent evidence suggests that in about 70% of fetuses with trisomy 21 the nasal bone is not visible at the 11-13(+6) week scan and that the frequency of absence of nasal bone differs in different ethnic groups. In addition, there is a relationship between absent nasal bone and nuchal translucency thickness.

Evidence-based obstetric ethics and informed decision-making by pregnant women about invasive diagnosis after first-trimester assessment of risk for trisomy 21.

Objective: The purpose of this study was to determine the ability of pregnant women to incorporate sophisticated screening information about risk assessment into their decisions about invasive testing in an appropriate way.

Study Design: Assessment of risk for trisomy 21 was carried out by a combination of maternal age, fetal nuchal translucency (NT) thickness, and maternal serum free beta-human chorionic gonadotrophin (hCG) and pregnancy-associated plasma protein-A (PAPP-A) at 11 to 13+6 weeks. The patients were counseled with regards to their estimated risk, and were informed that the only way to know for sure whether or not the fetus has a chromosomal abnormality is by having an invasive test, but these tests carry a risk of miscarriage of about 1%.

Prospective first-trimester screening for trisomy 21 in 30,564 pregnancies.

Objective: This study was undertaken to evaluate the performance of a 1-stop clinic for first-trimester assessment of risk (OSCAR) for trisomy 21 by a combination of maternal age, fetal nuchal translucency (NT) thickness, and maternal serum-free ss- human chorionic gonadotrophin (hCG) and pregnancy-associated plasma protein-A (PAPP-A).

Study Design: OSCAR was carried out in 30,564 pregnancies at 11 to 13 + 6 weeks. Patient-specific risks for trisomy 21 and detection and false-positive rates were calculated.