First-Trimester Down Syndrome Screening

Nuchal translucency measurement in first trimester Down syndrome screening.

(1) Approximately three in every four fetuses with Down syndrome have increased nuchal translucency (NT), which is a larger than normal build-up of fluid at the back of the neck. (2) The ultrasound measurement of NT between 11 and 14 weeks' gestation, in combination with the mother's age and the levels of placental biochemical markers in her blood, can be used to detect approximately 84% of fet...

First-trimester screening for Down's syndrome.

The aim of the present study was to evaluate the efficacy of the first trimester screening for Down syndrome (DS) in an unselected low-risk Finnish population. The study involved 4,617 women who attended screening between the 8th and 14th weeks of pregnancy in 1998-2000. They gave a blood sample for the measurement of pregnancy associated plasma protein A (PAPP-A) and free beta human chorionic ...

Advances in prenatal screening for Down syndrome: II first trimester testing, integrated testing, and future directions.

BACKGROUND The acceptability of prenatal screening and diagnosis of Down syndrome is dependent, in part, on the gestational age at which the testing is offered. First trimester screening could be advantageous if it has sufficient efficacy and can be effectively delivered. ISSUES Two first trimester maternal serum screening markers, pregnancy-associated plasma protein-A (PAPP-A) and free beta-...

Nuchal translucency and first trimester biochemical markers for Down syndrome screening: a cost-effectiveness analysis

Role of second-trimester genetic sonography after Down syndrome screening.

OBJECTIVE To estimate the effectiveness of second-trimester genetic sonography in modifying Down syndrome screening test results. METHODS The First and Second Trimester Evaluation of Risk (FASTER) aneuploidy screening trial participants were studied from 13 centers where a 15- to 23-week genetic sonogram was performed in the same center. Midtrimester Down syndrome risks were estimated for fiv...