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Flashcards in Genetic Screens Deck (58)
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1
Q

What is the purpose of the prenatal screen?

A

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

2
Q

Does screening r/o a disease?

A

no

3
Q

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

A

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

4
Q

What are the three major genetic screens done?

A

T21, T18, and T13

5
Q

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

A
  • hCG
  • PAPP-A
  • Nuchal translucency
6
Q

What does nuchal translucency measure? When can this be measured

A

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

7
Q

What is the PAPP-A test?

A

Pregnancy associated plasma protein

8
Q

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

A

85% sensitive

5% false positive

9
Q

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

A

Genetic counseling, and diagnostic CVS or amniocentesis

10
Q

What is the advantage of the 1st trimester screen?

A

Decisions can be made regarding continuing the pregnancy, if necessary

11
Q

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

A

As early at 10 weeks

-Needle is passed through the cervix into the chorion, and sample is gathered

12
Q

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

A
  • 15-20 weeks

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

13
Q

When can percutaneous umbilical blood sampling be performed?

A

20 weeks

14
Q

What are the complications with amniocentesis?

A
  • Pregnancy loss

- Break water.

15
Q

Why is amniocentesis particularly important for 35 yo mothers?

A

Risk of diagnosing disorder = risk of having disorder

16
Q

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

A
  • Percutaneous umbilical blood sampling

- After 20 weeks

17
Q

Can US be used alone for aneuploidy?

A

Yes

18
Q

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?

A

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
Q

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

A
  • MSAFP
  • Estriol
  • hCG
  • Inhibin A
20
Q

When is US for anatomy performed?

A

22 weeks (2nd trimester)

21
Q

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

A

No–false positives,

22
Q

When is 2nd trimester screening performed?

A

15-20 weeks

23
Q

What is the relation between maternal AFP and T21?

A

Low AFP increases risk for T21

24
Q

What is the sensitivity of T21 with the quad screen?

A

80%

25
Q

What is integrated screening?

A

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
Q

What is the sensitivity of the integrated screen?

A

94-96%

27
Q

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

A
  • BRCA1 and 2

- HNPCC

28
Q

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

A

Family history

29
Q

What FMHx is concerning for gyn cancer? (4)

A
  • 1st degree relative
  • young ages (less than 50)
  • CA in multiple generations
  • Many CAs in one individual
30
Q

What is Fitz-hugh-curtis syndrome?

A

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

31
Q

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

A
  • Increased screening (e.g. MRI in addition to annual mammogram)
  • Risk reduction surgery
32
Q

What is HNPCC? Inheritance pattern?

A

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

33
Q

What are “variants of undetermined significance” in terms of genetic testing?

A

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
Q

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

A

increased risk for colorectal and endometrial CA

35
Q

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

A

type A + ovarian, gastric, and pancreatic

36
Q

What is the puerperium?

A

First 6 weeks after delivery, including time in the hospital

37
Q

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

A
  • MMR
  • TDaP
  • flu
38
Q

Why do postpartum women need good breast support?

A

Breasts will engorge until painful

39
Q

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

A

Progesterone, since estrogen will decrease lactation

40
Q

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

A

Risk for VTE

41
Q

What are the common complications in the puerperium?

A
  • wound infx/separation

- Endomyometritis

42
Q

What is a dehiscence vs separation?

A

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

43
Q

What is endomyometritis?

A

Infection of the endometrium following pregnancy

44
Q

How common are UTIs postpartum

A

Common

45
Q

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

A
  • Brain (depression)
  • Breast
  • Bladder
  • Bleeding (lochia)
  • Birth control
46
Q

What is the incidence of postpartum depression?

A

5-25%

47
Q

How quickly does postpartum depression resolve?

A

7 months if untreated

48
Q

How long do the “baby blues” last for?

A

10 days ish

49
Q

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

A

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

50
Q

How long should pelvic rest postpartum last?

A

6 weeks

51
Q

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

A

3 weeks

52
Q

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

A

True

53
Q

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

A

45

54
Q

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

A

50

55
Q

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

A

3

56
Q

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

A

60

57
Q

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

A

True

58
Q

What is Lochia? How long does this last for?

A

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