Learning Objectives and CME/Disclosure Information

This activity is intended for healthcare providers delivering care to women and their families.

After completing this activity, the participant should be better able to:

1. List common physical findings seen in Down syndrome
2. Counsel parents on what to expect regarding social interactions related to Down syndrome

Estimated time to complete activity: 0.25 hours

Faculty:

Susan J. Gross, MD, FRCSC, FACOG, FACMG President and CEO, The ObG Project

Disclosure of Conflicts of Interest

Postgraduate Institute for Medicine (PIM) requires faculty, planners, and others in control of educational content to disclose all their financial relationships with ineligible companies. All identified conflicts of interest (COI) are thoroughly vetted and mitigated according to PIM policy. PIM is committed to providing its learners with high quality accredited continuing education activities and related materials that promote improvements or quality in healthcare and not a specific proprietary business interest of an ineligible company.

The PIM planners and others have nothing to disclose. The OBG Project planners and others have nothing to disclose.

Faculty: Susan J. Gross, MD, receives consulting fees from Cradle Genomics, and has financial interest in The ObG Project, Inc.

Planners and Managers: The PIM planners and managers, Trace Hutchison, PharmD, Samantha Mattiucci, PharmD, CHCP, Judi Smelker-Mitchek, MBA, MSN, RN, and Jan Schultz, MSN, RN, CHCP have nothing to disclose.

Method of Participation and Request for Credit

Fees for participating and receiving CME credit for this activity are as posted on The ObG Project website. During the period from Dec 31 2017 through Jan 25 2023, participants must read the learning objectives and faculty disclosures and study the educational activity.

If you wish to receive acknowledgment for completing this activity, please complete the test and evaluation. Upon registering and successfully completing the test with a score of 100% and the activity evaluation, your certificate will be made available immediately.

Joint Accreditation Statement

In support of improving patient care, this activity has been planned and implemented by the Postgraduate Institute for Medicine and The ObG Project. Postgraduate Institute for Medicine is jointly accredited by the Accreditation Council for Continuing Medical Education (ACCME), the Accreditation Council for Pharmacy Education (ACPE), and the American Nurses Credentialing Center (ANCC), to provide continuing education for the healthcare team.

Physician Continuing Medical Education

Postgraduate Institute for Medicine designates this enduring material for a maximum of 0.25 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Continuing Nursing Education

The maximum number of hours awarded for this Continuing Nursing Education activity is 0.2 contact hours.

Read Disclaimer & Fine Print

WHAT IS IT?

• Down syndrome is the most common chromosomal cause of intellectual disability
• May affect almost every organ system but the following findings are particularly common and may be identified on prenatal sonogram:
  • Increased nuchal translucency (first trimester) and/or nuchal fold (second trimester) or cystic hygroma
  • Congenital heart disease (50%), particularly AV canal defects
  • Duodenal atresia (double bubble sign) usually identified in 3rd trimester
  • Prenatal ultrasound markers include: short femurs, echogenic intracardiac foci, dilated renal pelviectasis, mild ventriculomegaly
• Other findings may not be apparent until postnatal life:
  • Dysmorphic features: epicanthal folds, single palmar crease, low set ears
  • Decreased muscle tone
  • Intellectual disability: usually in the mild (IQ ~70) to moderate range (IQ ~50)
    • Most individuals with Down syndrome can participate in numerous group and individuals activities, but may need some level of supervision throughout their lives
    • Individualized education programs can help children with Down syndrome reach their potential
    • Special education services at school can range from inclusion in the typical classroom with extra help to small group instruction
  • Hearing loss (up to 75%)
  • Sleep apnea (50-75%)
  • Eye disease, such as cataracts (50-70%)
  • Endocrine disease: thyroid, diabetes
  • Hirschsprung disease
  • Leukemia is slightly increased in this population, typically requiring lower doses of chemotherapy treatments
  • Plaques are frequently seen in older adults with Down syndrome (50+ years) but their presence does not mean that Alzheimer’s disease will necessarily develop – other treatable causes of decline are investigated first

CAUSE:

Down syndrome (DS) is a condition caused by the presence of an extra chromosome (#21) at the time of conception. In 90% of cases, it is the result of nondisjunction during meiosis (Trisomy 21), which is usually a sporadic occurrence. In 4-5% of DS affected individuals a chromosomal imbalance is the cause, inherited from a parent who has a balanced karyotype (i.e. Robertsonian translocation). A small proportion of affected individuals, < 1%, are diagnosed with mosaic DS.

KEY POINTS:

• ACOG requires all women be offered prenatal screening (biochemical/cfDNA) or invasive testing (amniocentesis;CVS) to detect an increased risk for DS, or to diagnosis it, respectively
• Children with Down syndrome are more similar to other children than they are different
• Overall, this condition is present in approximately 1 in 800 live births. Risk increases with maternal age
  • At maternal age 25, the risk is 1/1250
  • At maternal age 35, the risk is 1/365
  • At maternal age 40, the risk is 1/110
  • At maternal age 45, the risk is 1/32
• If there is a family history or previous DS pregnancy, refer for genetic counseling
• Data is limited on obstetrical management of an ongoing pregnancy with trisomy 21
  • Increased risk of fetal loss (5.9%), growth restriction (17.5%) and anomalies (75.0%)
  • Non-reassuring fetal surveillance (35.9%) appears to be associated with placental insufficiency and not necessarily related to structural anomalies
  • Data suggests a role for antepartum surveillance

Note: ACMG provides healthcare professionals with open access ‘ACT Sheets’ to guide next steps following a positive NIPS report for trisomy 21 (see ‘Learn More – Primary Sources’ below) 

Learn More – Primary Sources:

ACOG Practice Bulletin 226: Screening for Fetal Chromosomal Abnormalities

ACMG: Noninvasive Prenatal Screening via Cell-Free DNA [Trisomy 21: Positive Cell Free DNA Screen]

Antepartum management and obstetric outcomes among pregnancies with Down syndrome from diagnosis to delivery

CDC: Facts about Down syndrome

lettercase.org: Understanding a Down syndrome Diagnosis

Practice Guidelines for Communicating a Prenatal or Postnatal Diagnosis of Down Syndrome: Recommendations of the National Society of Genetic Counselors

Locate a Genetic Counselor or Genetics Services:

Genetic Services Locator-ACMG

Genetic Services Locator-NSGC

Genetic Services Locator-CAGC

Related ObG Topics:

Cystic Hygroma: Definition, Genetics and Prognosis

Atrial Septal Defect (ASD) – Summary and Implications

Duodenal Atresia – When the “Double Bubble” is Observed on Fetal Ultrasound

Short Femur on the Second Trimester Ultrasound Report: What to Include in the Management Plan?

Mild Cerebral Ventriculomegaly on Prenatal Ultrasound – Next Steps and Clinical Implications

Intellectual Disability Defined

The Chromosome – Structure and Number

Genetic Counseling: Who to Refer and What They Should Expect