IN THE NAME OF GOD

1. IN THE NAME OF GOD

2. Prenatal screening E . ZAREAN Fellowship of perinatology

3. Congenital Disorder • Genetic • Chromosomal • Enviromental • Infection • Morphogenesis defect

4. Baseline Risk for Having a Child With a Serious Birth Defect 3-5%

6. First and Second Trimester Screening

7. Prenatal Testing Screening versus Diagnosis First trimester versus Second trimester Serum and/or Ultrasound Low-risk versus High-risk Women

8. (-) (+) Diagnostic versus Screening No overlap: Positive test is abnormal Overlap: Positive test could be normal or abnormal

9. Is Prenatal Testing for Everyone?

10. consult • An explanation of the difference between a screening test and a diagnostic test. • Screening sensitivity and specificity compared to diagnostic testing. • Description of the performance of various screening tests . • The risks associated with prenatal diagnosis • The psychological implications of prenatal screening and diagnosis .

11. The implications of having a child with Down syndrome . • The detection rate of chromosomal abnormalities other than Down syndrome, and the implications of having a child with one of these abnormalities . • Information about the length of time necessary to obtain results from screening and diagnostic testing . • Information about pregnancy termination .

12. Screening Performance: The challenge in screening is to have a test that has a high detection rate and low false positive rate. Detection Rate : percentage of affecteds called (sensitivity) screen positive by the test The higher the better! False Positive Rate : percentage of unaffecteds called (1 – specificity) screen positive by the test The lower the better!

13. First trimester Screening Nuchal translucency Free beta HCG PAPP-A CombinedNT and Serum

14. Amnion Skin Nuchal Translucency (NT)

15. First Trimester US – Nasal Bone Nasal bone present in a euploid fetus in the first trimester Nasal bone absent in a fetus with T21in the first trimester

16. Nuchal Translucency (NT) Measurement “increased nuchal translucency” “normal nuchal translucency”

17. Second trimester screening • AFP • B-HCG • Unconjucated estriol • Inhibin A

18. Contingent

19. Positive screen test • Most parents are anxious because they do not fully understand that most positive results are associated with a normal pregnancy outcome. • after than negative diagnostic test some anxiety related to the false-positive screening test may persist . • On the other hand, normal results may have psychological benefits for the reassured parents.

20. Consult : DR – FPR – Advantage – Disadvantage • Multiple pregnancy

21. Case 1 • Age 27 • 8 weeks pregnant • G2P1 • Previous pregnancy uncomplicated • Married for 5 years, healthy 3 year old daughter

22. Case 1 • What prenatal genetic screening options would you discuss with her? • Discuss options with benefits, limitations, availability. • New screening tests may require earlier first prenatal visit .

23. Case 1 • If she was 38…..? • Could go directly to CVS, amnio • Combined /Integrated test more accurate than age . • What might affect her decision? • Miscarriage rate . • Performance of amnio/CVS compared to sequential test. • May detect problems other than Down syndrome . • Her perception of risk/morbidity associated with Down syndrome. • Her personal/family/religious beliefs…

24. Case 2 • Age 34 • 17 weeks pregnant • To discuss result of integrated screen.

25. Case 2 • Results: COMMENTS AND RECOMMENDATIONS Down syndrome: The risk of Down syndrome is GREATER than the screening cut-off of 1 in 250 at term. If the gestational age is confirmed, counselling regarding the risks and benefits of AMNIOCENTESIS is suggested.

26. Case 3 • 33 years old • G2P0 • Miscarriage last year • Trying to get pregnant for several years • 14 weeks pregnant • Following U/S for NT . you received report from radiologist indicating NT is elevated (4.0mm) for this gestational age • What would be important to discuss with her and her partner at this time?

27. Case 3 • she was referred for genetic counselling • Offered: • Chromosome testing • Ultrasound 18 - 20 wks & echocardiogram 20 - 22 wks • Counselled risk of miscarriage with CVS or amniocentesis. • May be even more significant for this couple in view of infertility and miscarriage

31. High AFP • Over than 2 MOM : twin pregnancy incorrect GA ovarian tumor hepatocellular tumor IUFD low birth weight Placenta abruptio

32. Anomaly open NTD omphalocele ( 4 MOM ) gastroschisis (10 MOM ) teratoma cystic hygroma benign obstructive uropathy fetal edema skin defect

33. ultrasonography The sensitivity, specificity, and positive and negative predictive values of ultrasound evaluation for the detection of NTDs were 98, 100, 100, and 99.9 percent, respectively .

34. prenatal diagnostic procedure for fetal karyotype, rather than serum screening A previous pregnancy complicated by fetal trisomy . At least one major or two minor fetal structural anomalies in the current pregnancy . Chromosomal translocation, inversion, or aneuploidy in themselves or their partner .

35. Future Directions First trimester US alone 3D/4D US Noninvasive Isolation of fetal DNA

36. دستورالعمل کشوری

37. مشاوره بايد در اولين ملاقات بارداري (هفته 6 تا 10 بارداري) انجام شود.

38. درحال حاضر غربالگري جنين در سه ماهه اول بارداري توصيه مي شود. چنانچه خانم باردار پس از 13 هفته و 6 روز و قبل از هفته 17 بارداري مراجعه نمايد و غربالگري سه ماهه اول را انجام نداده است، پس از مشاوره و انتخاب والدين، غربالگري سه ماهه دوم بارداري درخواست مي شود.

40. QUESTIONS ??