Prenatal screening ppt

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson
Download our mobile app to listen on the go
Get App

Questions and Answers

What is the primary benefit of prenatal screening for chromosomal abnormalities?

  • Guaranteed detection of all abnormalities
  • Parental reassurance if normal (correct)
  • Increased risk of miscarriage
  • Immediate delivery if an abnormality is detected

What percentage of pregnancies have recognizable chromosomal abnormalities?

  • 1 in 200
  • 1 in 100
  • 1 in 400
  • 1 in 300 (correct)

Which screening method is noted as the most sensitive and specific for detecting fetal aneuploidies?

  • Chorionic villus sampling
  • Cell-Free DNA testing (correct)
  • First trimester screening
  • Quad screening

What is a common risk associated with abnormal prenatal screening results?

<p>Increased anxiety among parents (D)</p> Signup and view all the answers

Which statistical finding is most common among recognized chromosomal abnormalities?

<p>Trisomy 21 (A)</p> Signup and view all the answers

What percentage of recognized chromosomal abnormalities are accounted for by Trisomy 21, 18, and 13?

<p>95% (D)</p> Signup and view all the answers

What should be offered if an abnormal screening test is identified?

<p>Genetic counseling and further testing (A)</p> Signup and view all the answers

What is a significant risk of prenatal screening and diagnosis?

<p>False positive results (C)</p> Signup and view all the answers

What chromosomal condition is associated with the absence of the fetal nasal bone during the first trimester?

<p>Down syndrome (trisomy 21) (D)</p> Signup and view all the answers

What is the risk of neural tube defects in pregnancies involving patients with a personal history of a pregnancy with an NTD?

<p>1/30 pregnancies (B)</p> Signup and view all the answers

Which of the following substances is a component of quad screening for neural tube defects?

<p>Pregnancy-associated plasma protein A (A), Estriol (B), HCG (C)</p> Signup and view all the answers

At what gestational age can chorionic villus sampling (CVS) be performed?

<p>10-13 weeks (B)</p> Signup and view all the answers

What is the main purpose of the first trimester serum screening?

<p>To evaluate chromosomal abnormalities (B)</p> Signup and view all the answers

Which group should receive daily folic acid requirements of 4 mg during pregnancy?

<p>At-risk pregnancies (A)</p> Signup and view all the answers

What does a positive screening test for fetal aneuploidy indicate?

<p>A need for genetic counseling and comprehensive ultrasound evaluation (C)</p> Signup and view all the answers

Which procedure is diagnostic for genetic conditions and involves a miscarriage risk?

<p>Amniocentesis (A)</p> Signup and view all the answers

When is the second trimester ultrasound typically performed for assessing fetal structural defects?

<p>18-22 weeks (C)</p> Signup and view all the answers

Which factor does NOT increase the risk of neural tube defects?

<p>Adequate folic acid intake (A)</p> Signup and view all the answers

What is a key consideration for patients when offered prenatal genetic screening and diagnostic testing?

<p>Patients have the right to pursue or decline any prenatal testing. (A)</p> Signup and view all the answers

Which of the following factors is associated with an increased risk of chromosomal abnormalities in pregnancies?

<p>Increasing maternal age (B)</p> Signup and view all the answers

What is a potential consequence of receiving an abnormal prenatal screening result?

<p>Increased parental anxiety and further testing options (B)</p> Signup and view all the answers

The quad screening conducted during the second trimester assesses for which of the following?

<p>Down syndrome, Trisomy 18, and neural tube defects (A)</p> Signup and view all the answers

What is an important limitation associated with the cell-free DNA screening method?

<p>False negatives can occur, potentially leading to missed conditions. (C)</p> Signup and view all the answers

Flashcards

Prenatal Screening

Tests done during pregnancy to detect potential chromosomal abnormalities or other conditions in the fetus.

Chromosomal abnormalities

Problems with the number or structure of chromosomes, often leading to developmental issues.

Trisomy 21

A condition where an individual has three copies of chromosome 21, leading to Down Syndrome.

Maternal age

The age of the pregnant woman.

Signup and view all the flashcards

Cell-Free DNA (cfDNA)

A maternal blood test that analyzes fetal DNA to detect potential chromosomal disorders.

Signup and view all the flashcards

First Trimester Screening

Prenatal testing that takes place during the first three months of a pregnancy.

Signup and view all the flashcards

Nuchal Translucency (NT)

An ultrasound measurement of the fluid build-up at the back of the fetal neck; used as a screening tool for certain chromosomal abnormalities

Signup and view all the flashcards

PAPP-A and hCG

Blood tests that indicate possible fetal issues, often used with NT screening; in first trimester screening.

Signup and view all the flashcards

Second Trimester Screening

Prenatal testing that usually takes place during the second three months.

Signup and view all the flashcards

Quad Screening

Includes blood test to determine the risk of fetal abnormalities.

Signup and view all the flashcards

Amniocentesis

A diagnostic procedure that involves taking amniotic fluid samples to analyze fetal cells.

Signup and view all the flashcards

CVS (Chorionic Villus Sampling)

Another diagnostic procedure done earlier in pregnancy that analyzes placental tissue for chromosomal abnormalities.

Signup and view all the flashcards

Cell-free DNA (cfDNA) prenatal screening

A blood test that analyzes fetal DNA in a pregnant person's blood to check for chromosomal abnormalities.

Signup and view all the flashcards

Fetal abnormalities screened by cfDNA

Down syndrome, Edwards syndrome, Patau syndrome, and sex chromosome issues.

Signup and view all the flashcards

First Trimester Screening

Nuchal translucency (NT) measurement and maternal blood tests.

Signup and view all the flashcards

Nuchal Translucency (NT)

A widening of the translucent area of the posterior neck in a first trimester embryo.

Signup and view all the flashcards

Fetal Nasal Bone

An indicator of chromosomal abnormalities (often trisomy 21).

Signup and view all the flashcards

Second Trimester PN screening

Ultrasound for structural defects plus maternal serum testing.

Signup and view all the flashcards

Neural Tube Defects (NTD)

Birth defects affecting the brain and spinal cord.

Signup and view all the flashcards

Risk factors for Neural Tube Defects (NTD)

Low folic acid, seizure medications, diabetes, and genetics.

Signup and view all the flashcards

Folic Acid in Pregnancy

Crucial for preventing neural tube defects.

Signup and view all the flashcards

Quad screening

Second trimester blood test for NTD screening.

Signup and view all the flashcards

Chorionic villus sampling (CVS)

A first trimester procedure to analyze fetal chromosomes, definitive diagnosis.

Signup and view all the flashcards

Amniocentesis

A second trimester procedure to analyze fetal chromosomes, definitive diagnosis.

Signup and view all the flashcards

Prenatal screening

Tests done during pregnancy to find potential problems with the fetus, often focusing on chromosome issues.

Signup and view all the flashcards

Chromosomal abnormalities

Problems with the number or structure of chromosomes, sometimes leading to health issues.

Signup and view all the flashcards

Trisomy 21

A condition where an individual has three copies of chromosome 21, a key cause of Down syndrome.

Signup and view all the flashcards

Maternal age & risk

Older pregnant people have a higher chance of having a baby with a chromosomal issue.

Signup and view all the flashcards

Cell-Free DNA (cfDNA)

A maternal blood test that can look for fetal DNA to see if chromosome issues exist, first trimester screening option.

Signup and view all the flashcards

First Trimester Screening

Prenatal testing during the first three months; often includes ultrasound and blood tests.

Signup and view all the flashcards

Nuchal Translucency (NT)

An ultrasound measurement of fluid buildup behind the fetal neck, part of first trimester screening.

Signup and view all the flashcards

PAPP-A and hCG

Blood tests in the first trimester for prenatal screening, often used with NT.

Signup and view all the flashcards

Second Trimester Screening

Prenatal testing typically done during the middle of pregnancy.

Signup and view all the flashcards

Quad Screening

Includes tests like AFP, inhibin-A, hCG, and estriol in the second trimester.

Signup and view all the flashcards

Amniocentesis

Diagnostic procedure to analyze amniotic fluid for fetal chromosome analysis.

Signup and view all the flashcards

Chorionic Villus Sampling (CVS)

A first trimester procedure to analyze placental tissue for chromosome issues.

Signup and view all the flashcards

Diagnostic tests

Tests that definitively identify a fetal condition, like amniocentesis or CVS.

Signup and view all the flashcards

Study Notes

Prenatal Screening for Chromosomal Abnormalities

  • Approximately 1 in 300 pregnancies have detectable chromosomal abnormalities.
  • Most common abnormalities are Trisomy 21 (Down syndrome), Trisomy 18, Trisomy 13, and X/Y chromosome changes.
  • Maternal age is a significant risk factor for chromosomal abnormalities.
  • Many pregnancies with chromosomal abnormalities do not reach the second trimester.

Prenatal Screening/Testing Recommendations

  • All pregnant individuals should be offered prenatal genetic screening and diagnostic testing, regardless of age or risk factors.
  • Decisions about screening and diagnostic testing are the patient's choice.
  • Individuals with positive screening results should receive genetic counseling and invasive diagnostic testing for genetic conditions, as well as a comprehensive ultrasound (18-22 weeks).

Risk Assessment (Down Syndrome)

  • Down syndrome is a more prevalent chromosomal abnormality among fetuses in the third trimester.

Benefits of Prenatal Screening/Diagnosis

  • Provides reassurance (if results are normal).
  • Allows for knowledge of chromosomal/other abnormalities.
  • Offers increased options for management, including further testing, referrals, and counseling for planned birth or termination.
  • Prepares for a child with special needs.
  • Aids in obstetric/neonatal management.

Risks of Prenatal Screening/Diagnosis

  • Potential for parental anxiety (from abnormal results).
  • Possibility of false positive results.
  • Risk of pregnancy complications such as premature rupture of membranes (PROM), infection, preterm labor (PTL).
  • Risk of pregnancy loss.

Prenatal Screening Options

  • Cell-free DNA (cfDNA): Maternal blood test detecting fetal DNA for common aneuploidies, including Down syndrome, Edwards syndrome, Patau syndrome, and sex chromosome abnormalities. Sensitive and specific, but not definitive, false negatives are possible, and can be performed as early as 10 weeks.
  • First Trimester Screening: Nuchal translucency (NT) ultrasound and maternal serum markers (β-hCG and PAPP-A) to calculate chromosomal abnormality risk.
    • Nuchal translucency: Widening of posterior neck area in the embryo is a sign of potential abnormality
    • Nasal bone: Absence of a nasal bone can indicate chromosomal abnormalities.
  • Second Trimester Screening: Quadruple screening (AFP, inhibin-A, hCG, estriol) and anatomical ultrasound to evaluate for structural defects.

Neural Tube Defects (NTDs)

  • Approximately 1 in 1,000 pregnancies involve NTDs. NTD risk is higher in patients with prior NTD pregnancies.
  • Risk factors include low folic acid intake, seizure medications, diabetes, and genetic predisposition.
  • Folic Acid Recommendations: 400 mcg daily for typical pregnancies; 4,000 mcg daily for pregnancies at high risk (prior NTD, seizure disorders, diabetes, family history).
  • Screening: Quadruple screening and second-trimester ultrasound (18-22 weeks).
  • Diagnostic: Chorionic villus sampling (CVS) or amniocentesis.

Diagnostic Tests

  • Chorionic villus sampling (CVS): First trimester procedure (10-13 weeks) with a miscarriage risk of 1/100-1/200
  • Amniocentesis: Second trimester procedure (15-22 weeks) with a miscarriage risk of 1/200-1/500

Trimester Breakdown

  • First trimester: Weeks 1-13
  • Second trimester: Weeks 14-27
  • Third trimester: Weeks 28-40

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser