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Flashcards in Genetic Screens Deck (58):
1

What is the purpose of the prenatal screen?

Define the risk of a genetic disease in a low risk population

2

Does screening r/o a disease?

no

3

What is the difference between a diagnostic test and a screening test?

A screening test does not confirm or r/o a disease, but assesses the risk that a child may have a genetic disease

4

What are the three major genetic screens done?

T21, T18, and T13

5

What are the three biochemical markers tested for in the 1st trimester?

-hCG
-PAPP-A
-Nuchal translucency

6

What does nuchal translucency measure? When can this be measured

The size of the fluid at the back of the fetal neck that can bee seen at 10-14 weeks

7

What is the PAPP-A test?

Pregnancy associated plasma protein

8

What is the sensitivity of US and markers in the 1st trimester for Down syndrome? False positive rate?

85% sensitive

5% false positive

9

If there is an increased risk of aneuploidy with the 1st trimester screen, what is offered?

Genetic counseling, and diagnostic CVS or amniocentesis

10

What is the advantage of the 1st trimester screen?

Decisions can be made regarding continuing the pregnancy, if necessary

11

How early can CVS (chorionic villus sampling) be performed? What is done with this procedure?

As early at 10 weeks
-Needle is passed through the cervix into the chorion, and sample is gathered

12

How early can amniocentesis *for genetics* be performed? What is done with this procedure?

-15-20 weeks
-needle passed through SQ tissue of mom into uterus/amnion, to gather skin samples for karyotyping

13

When can percutaneous umbilical blood sampling be performed?

20 weeks

14

What are the complications with amniocentesis?

-Pregnancy loss
-Break water.

15

Why is amniocentesis particularly important for 35 yo mothers?

Risk of diagnosing disorder = risk of having disorder

16

How do you get blood sample from a fetus (for typing/screen and/or karyotyping)? When is this performed?

-Percutaneous umbilical blood sampling
-After 20 weeks

17

Can US be used alone for aneuploidy?

Yes

18

If US is performed alone, what are the signs that may signal increased risk for chromosomal abnormality? (2) What should be done if these are detected?

Structural malformation of a major fetal organ or structure, OR finding 2+ minor malformations

Genetic testing of the fetus regardless of maternal age or parental karyotype

19

What are the components of the quad screen that can be done to confirm karyotypes?

-MSAFP
-Estriol
-hCG
-Inhibin A

20

When is US for anatomy performed?

22 weeks (2nd trimester)

21

Should women who have had 1st trimester screening for aneuploidy, undergo 2nd trimester screening? Why?

No--false positives,

22

When is 2nd trimester screening performed?

15-20 weeks

23

What is the relation between maternal AFP and T21?

Low AFP increases risk for T21

24

What is the sensitivity of T21 with the quad screen?

80%

25

What is integrated screening?

Results of both 1st and 2nd trimester screen and US combined to increase the ability to detect Down syndrome--these results are withheld until both tests are completed?

26

What is the sensitivity of the integrated screen?

94-96%

27

What are the two genetic cancer screens that are commonly obtained in ob/Gyn?

-BRCA1 and 2
-HNPCC

28

The most important initial step in identifying women at high risk for hereditary cancers is through what?

Family history

29

What FMHx is concerning for gyn cancer? (4)

-1st degree relative
-young ages (less than 50)
-CA in multiple generations
-Many CAs in one individual

30

What is Fitz-hugh-curtis syndrome?

Adhesions between the liver and the diaphragm d/t PID spread

31

If a woman tests positive for the BRCA mutation, what should be done? (2)

-Increased screening (e.g. MRI in addition to annual mammogram)
-Risk reduction surgery

32

What is HNPCC? Inheritance pattern?

AD defect in DNA mismatch repair, that increases the risk for colon and endometrial CA

33

What are "variants of undetermined significance" in terms of genetic testing?

Gene that is found, but is of uncertain significance--if these are later found to be at an increased risk, then she will be contacted

34

What is Lynch A (type I ) at increased risk for?

increased risk for colorectal and endometrial CA

35

What is Type B (Lynch II) at increased risk for?

type A + ovarian, gastric, and pancreatic

36

What is the puerperium?

First 6 weeks after delivery, including time in the hospital

37

What are the vaccines that are updated in the hospital after delivery?

-MMR
-TDaP
-flu

38

Why do postpartum women need good breast support?

Breasts will engorge until painful

39

What is the appropriate hormonal birth control in recently postpartum women? Why?

Progesterone, since estrogen will decrease lactation

40

Why should oral contraceptives, as well as sexual intercorse, be done a few weeks later after being postpartum, instead of right after birth?

Risk for VTE

41

What are the common complications in the puerperium?

-wound infx/separation
-Endomyometritis

42

What is a dehiscence vs separation?

Dehiscence is when the fascia pulls apart, whereas in wound separation there is no fascial disturbances

43

What is endomyometritis?

Infection of the endometrium following pregnancy

44

How common are UTIs postpartum

Common

45

What are the 5 B's of the immediate postpartum period?

-Brain (depression)
-Breast
-Bladder
-Bleeding (lochia)
-Birth control

46

What is the incidence of postpartum depression?

5-25%

47

How quickly does postpartum depression resolve?

7 months if untreated

48

How long do the "baby blues" last for?

10 days ish

49

What is the diagnostic criteria for postpartum depression? (start, end)

Onset within 4 weeks postpartum, and lasting up to 7 months

50

How long should pelvic rest postpartum last?

6 weeks

51

Combination OCPs should not be started until at least how many weeks postpartum?

3 weeks

52

True or false: a personal h/o ovarian cancer is a qualification to receive genetic testing for BRCA-1?

True

53

1 family member dx with breast, ovarian, colon or uterine CA under what age qualifies one to receive genetic screening?

45

54

2 family members dx with breast, ovarian, colon or uterine CA, and 1 dx under what age qualifies one to receive genetic screening?

50

55

What number of family member diagnoses at any age is needed to qualify for genetic testing?

3

56

Triple negative breast cancer under what age qualifies for genetic screening?

60

57

True or false: a family h/o of 1 male breast cancer qualifies for genetic screening

True

58

What is Lochia? How long does this last for?

the vaginal discharge after giving birth (puerperium) containing blood, mucus, and uterine tissue. Lochia discharge typically continues for 4 to 6 weeks after childbirth.