Foundations of Perinatal Genetic Counseling

Amber Mathiesen, MS, LCGC, is a licensed and board-certified genetic counselor in prenatal genetics at University of Utah Health, co-director of the perinatal genetics course at the University of Utah's Graduate Program in Genetic Counseling, and a prenatal rotation supervisor. She also acts as a research committee member and mentor for various genetic counseling students.Kali Roy, MS, LCGC, is a perinatal genetic counselor at University of Utah Health and co-director of the perinatal genetics course at the University of Utah's Graduate Program in Genetic Counseling. She graduated from the University of Utah Graduate Program in Genetic Counseling and completed a Master's of Science in Human Genetics and Genomics at the University of Connecticut.

• Preface Acknowledgments Common Abbreviations 1. Pregnancy Basics 1.1 Pregnancy Timeline and Dating Pregnancies are Counted in WeeksGestational Age versus Embryonic AgeNormal Pregnancy Timeline and DurationMethods for DatingGuidelines and Recommendations for Determining DatingTools Available for Calculating Gestational Age 1.2 Pregnancy Care Types of Prenatal ProvidersRoutine Prenatal VisitsPrenatal PanelComplete Blood CountBlood Type and Antibody TestingHbA1c for DiabetesFetal ImagingComplicated Pregnancies 1.3 Documenting a Pregnancy History Gravida and ParaCalculating Gravidity and Parity (G's and P's) 2. The Perinatal Genetic Counseling Appointment and Family History 2.1 The Perinatal Genetic Counseling Session 2.2 Obtaining a Pregnancy History 2.3 Obtaining a Family History 2.4 Interpreting a Family History Mendelian ConditionsMultifactorial ConditionsConsanguinityBirth DefectsIntellectual Disability and AutismPregnancy Loss and InfertilityUnknown EtiologiesAccuracyOther Conditions (Referrals) 2.5 Unique Situations in the Perinatal Family History Gamete DonationSame Sex CouplesSurrogacyAdoptionEthnicity 3. Prenatal Screening 3.1 Evaluation of a Screen SensitivitySpecificityPositive Predictive ValueNegative Predictive ValuePersonal Utility 3.2 Prenatal Screening Options Maternal Serum Screening Multiples of the Median (MoM)Calculating the RiskTiming and Test OptionsResultsPattern AssociationFollow up of Abnormal ResultsLimitations of Maternal Serum Screening Cell Free DNA Testing Origin Fetal fraction Clearance Methodology Conditions Analyzed Test performance Who to offer testing to? Multiples and Vanishing Twins Adverse Pregnancy Outcomes Considerations Prior to Testing Results and Follow upResources 4. Prenatal Diagnosis 4.1 Techniques Chorionic Villus Sampling Twins Risks Limitations Amniocentesis Twins Risks 4.2 Testing Options KaryotypeFluorescence in situ Hybridization (FISH)MicroarrayMolecular TestingAFP &AChEOther Testing 4.3 Indications for Diagnostic Testing 5. Common Indications 5.1 Age Related Risks Maternal AgePaternal Age 5.2 Personal and Family History Single Gene ConditionsAneuploidyMultifactorial ConditionsBirth DefectsIntellectual Disability/Developmental Delay/AutismConsanguinity 5.3 Ultrasound Anomalies Counseling for Ultrasound Anomalies Classification of Ultrasound Findings Estimating Risks Ultrasound Findings in Pregnancies with Aneuploidy Down syndrome Trisomy 18 Trisomy 13 Turner Syndrome Triploidy Common Ultrasound Findings Hallmark Ultrasound Findings Associated with Genetic ConditionsOpen Neural Tube Defects 5.4 Teratogens 5.5 Recurrent Pregnancy Loss, Stillbirth, and Infertility Evaluation of Pregnancy Loss and Stillbirth Evaluation of Infertility Male Infertility Female Infertility 5.6 Preconception Counseling 6. Carrier Screening 6.1 Background Who Should be Offered Carrier Testing?Carrier Screening for Gamete DonorsTiming of ScreeningEvaluating RisksPositive Test ResultsNegative Results and Residual RisksOther Types of ResultsApplication of a High Risk ResultRepeat TestingNewborn Screening 6.2 Condition Directed or Ethnicity Based Testing Cystic FibrosisSpinal Muscular AtrophyFMR1-Related DisordersAshkenazi Jewish and French Canadian/CajunHemoglobinopathiesFamily History 6.3 Expanded Carrier Testing 7. Pregnancy Management 7.1 Reproductive Options Continuation of PregnancyAdoptionTermination First Trimester Second Trimester Later Term Twins 7.2 Pregnancy Management Referrals Maternal-Fetal Medicine SpecialistSpecialized Imaging 3D Ultrasound Echocardiography MRI CardiologyNeonatologyFetal Surgery/InterventionPediatric SurgeryPediatric SpecialistsPathology/AutopsyPalliative Care/Hospice 7.3 Support Referrals and Bereavement 8. Assisted Reproductive Technology and Reproductive Options for the At Risk Couple 8.1 Reproductive Options for At Risk Couples 8.2 Assisted Reproductive Techniques 8.3 Preimplantation Genetic Testing Preimplantation Genetic Screening (PGS)Preimplantation Genetic Diagnosis (PGD) 9. Common Perinatal Genetic Counseling Situations 9.1 Pregnancy Termination Misinterpreted IntentPatient Provider Conflict 9.2 Incidental Findings Misattributed PaternityDiscovery of ConsanguinityIdentification of an Incidental Condition 9.3 Privacy and Confidentiality Genetics is a Family AffairSecret Information 9.4 Working with couples Couples in Conflict"It's not my body" 9.5 Dealing with Uncertainty Fetal Diagnosis and PrognosisFamily HistoryComplex ConditionsVariants of Uncertain Significance 9.6 Fetal Sex Disclosure Patient's Desire to Know or NotTesting may Reveal Sex Chromosome Abnormalities (SCAs)Disorders Affecting a Specific SexTesting Only for SexFetal Sex may be "Difficult News" 9.7 Patient Questions "What would you do?"When You Don't Know the Answer 9.8 Testing a Fetus for Adult Onset Condition 9.9 Barriers for Consent Patient UnderstandingVoluntary Participation 9.10 Rapidly Evolving Technologies Appendix A Appendix B Index