Parental Diagnosis - increased risk for chromosomal...

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Parental Diagnosis Chorionic villus sampling (CVS) Involves biopsy of tissue from villous area of chorion transcervically or transabdominally, between 10 th and 12h weeks of pregnancy. Advantage : allows result to be available at an early stage of pregnancy, thus reducing period of uncertainty. *AFP cannot be assayed, and screening for open NTDs should be performed by maternal serum screening at 16 weeks of gestation. Amniocentesis Inserting a needle into amniotic sac and removing a sample of amniotic fluid transabdominally by syringe. Performed at 15 th to 16 th week after first day of last menstrual period. AFP can be assayed to detect NTDs. Amniotic fluid leakage was also more common with early amniocentesis. The leading indication for invasive fetal testing by amniocentesis or CVS is
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Unformatted text preview: increased risk for chromosomal aneuploidies because of advanced maternal age Non-invasive Maternal serum alpha-fetoprotein (MSADP): measured during second trimester as a screening for NTDs (trisomy, particularly in trisomy 21) 1 st Trimester screening: 11 and 13 weeks of gestation; relies on 1) quantifying levels of certain substance in maternal serum 2) measuring subcutaneous edema of the fetal neck by highly targeted ultrasonographic exam; Nuchal Translucency, pregnancy-associated plasmas protein A (PAPP-A), human chorionic gonadotropin (hCG) 2 nd Trimester screening: MSAFP, -hCG, un-conjugated estriol (this is referred as Triple Test , inhibin A Quad Test )...
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This note was uploaded on 01/24/2011 for the course STAT 250 taught by Professor Tba during the Spring '09 term at Purdue University-West Lafayette.

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