Maternal Serum Screening
Down Syndrome, Trisomy 18 and Neural Tube Defects
Sequential Screening
March 2011
Sequential screening is a type of cross trimester screening that has been introduced as a mean to increase the detection rate and provide the lowest false-positive rate. The markers used in the risk calculation include: NT and PAPP-A which are measured during the first trimester and AFP, unconjugated estriol, hCG and inhibin A which are measured in the second trimester.
In sequential screening, once NT and PAPP-A information is available, a risk calculation is performed. If the screen is positive, results are reported and this is considered the end of the screening test. In contrast, if the screen is negative, a second sample is collected in the second trimester and new risk estimate is generated.
Sequential Screening |
Jump to section:
- Introduction
- What is Maternal Serum Screening?
- Who Should Be Offered Maternal Serum Screening?
- Maternal Serum Screening: Options
- Maternal Serum Screening: Risk Calculation
- First Trimester Serum Screening
- Nuchal Translucency (NT)
- Nuchal Translucency (NT)
- Nuchal Translucency (NT)
- First Trimester Serum Screening
- First Trimester Screening
- Second Trimester Screening
- Second Trimester Screening
- Second Trimester Screening
- Sequential Screening
- Sequential Screening
- Sequential Screening
- Sequential Screening
- Mayo Medical Laboratories Maternal Serum Screening Options
- References
- Questions?
External
link
PDF
document
Excel
document
Word
document