Midterm- prenatal testing

Question 1

ABO Rh and Antibody screen

Answer 1

• blood type

- Rhesus type and antibody screening tests to detect antibodies potentially causing hemolytic disease of the newborn

Question 2

Hct or Hgb and MCV

Answer 2

• Anemia- IDA and pernicious anemia

- Thallasemia (more common)

Question 3

cervical cytology

Answer 3

-pap if due, not routine with pregnancy

Question 4

presence of rubella infection

Answer 4

-therapeutic abortion should be considered (esp.

Question 5

syphilis

Answer 5

test to prevent perinatal transmission of treponema pallidum

treat appropriately with positive test result

Question 6

hepatitis B surface antigen screening

Answer 6

to prevent perinatal transmission, screen all women, even if previously tested or vaccinated

Question 7

chlamydia and gonorrhea screening

Answer 7

• screen all pregnant women at 1st PN visit per CDC and ACOG
• USPSTF instead recommends limited screening for women 24 yr of age, and older women at incr risk
• causes conjunctivitis or pneumonia in infant

Question 8

best test for chlamydia and gonorrhea

Answer 8

NAAT (nucleic acid amplification tests)

-endocervix or vaginal swab preferred for PN care, urine testing, or liquid based cytology specimens

Question 9

thyroid function testing

Answer 9

• test at risk for thyroid dz (symptomatic women, personal or family hx, type 1 diabetes, etc)
• other experts say universal screening

Question 10

untreated thyroid dz may result in

Answer 10

fetal neurological abnormalities

Question 11

elevated thyroid peroxidase antibodies

Answer 11

testing is controversial - not routinely checked

Question 12

HIV screening

Answer 12

• done routinely early in pregnancy using “opt out” approach
• with retroviral treatment, transmission is reduced to 2% along with avoiding breastfeeding and labor
• resting 3rd trimester (

Question 13

Urine culture

Answer 13

• two consecutive voided urine specimens or a single catheterized urine specimen (not routinely done)
• pregnant women with untreated bacteriuria are at high risk for acquiring pyelonephritis, premature labor, low birth weight infants

Question 14

Down syndrome screening

Answer 14

• all women should be offered aneuploidy screening before 20 weeks of gestation
• women of any age at high risk of Down syndrome with the appropriate diagnostic procedure for fetal karyotype instead of screening tests

Question 15

First trimester combined test for Down Syndrome

Answer 15

• US for nuchal translucency (NT) and gestational age by crown rump length
• Serum pregnancy associated plasma protein (PAPP-A) and free or total hCG (9-13 weeks free hCG, 11-13 weeks total hCG)

Question 16

for those who screen positive for Down syndrome follow with

Answer 16

chorionic villi sampling (CVS) (extract a piece of the placenta through a catheter). diagnostic. do in first trimester

Question 17

Full integrated test

Answer 17

• Highest detection rate for Down’s syndrome, lowest screen positive
• US measurement NT at 10-13 weeks
• PAPP-A at 10-13 weeks
• Quadruple test at 15-18 weeks- (Alpha fetoprotein (AFP), unconjugated estriol (uE3), hCG, inhibin A)

Question 18

Serum integrated test

Answer 18

• Same as full integrated test without the US measurement of NT
• Used in areas where the woman does not have access to technicians who can adequately measure NT

Question 19

Quadruple test measures what?

Answer 19

serum AFP, uE3, hCG, and inhibin A

Question 20

Quadruple test performed when?

Answer 20

15-18 weeks gestation

Question 21

Genetic sonogram

Answer 21

18-20 weeks gestation

-not useful as primary screening test

Question 22

New DNA testing

Answer 22

maternal plasma DNA

Question 23

for those who screen positive follow with

Answer 23

CVS first trimester

Amniocentesis second timester

Question 24

varicella testing

Answer 24

• test all pregnant women for immunity

- if exposed during pregnancy, administer varicella zoster immune globulin (VariZIG prophylaxis)

Question 25

bacterial vaginosis

Answer 25

screening not recommended in routine prenatal care - if asx don’t need to treat
only treat sx

Question 26

herpes simplex virus

Answer 26

Routine testing generally not recommended in asymptomatic women
Type specific screening may be reasonable in asymptomatic partners in symptomatic men

Question 27

Chagas disease

Answer 27

Parasitic disease endemic to Latin America
Consider testing in women who lived in the area
Women may be asymptomatic and infection can be transmitted to the fetus

Question 28

Lead testing

Answer 28

Not usu tested, unless mother is thought to have exposure
Diagnosis
Lead levels 5mcg/dL- follow up is dependent upon levels
-Pediatrician should be told of mother’s lead levels at delivery
-Lead will cross the placenta, associated with miscarriage and still birth
-Breastfeeding-levels in breastmilk should be evaluated

Question 29

Ultrasound

Answer 29

US useful early in pregnancy to establish EDD
Randomized studies have shown good EDD reduce unnecessary inductions
First trimester US can detect fetal malformations and multiple pregnancies earlier

Question 30

Neural Tube Defect Screening and Down Syndrome Screening

Answer 30

All women should be offered screening if not done in the first trimester

Question 31

Gestational Diabetes

Answer 31

All pregnant women should be screened at 24-28 weeks gestation
Consider first trimester screening with significant risk factors:
Obesity
Previous GD
Previous macrosomia

Question 32

Sexually transmitted Disease

Answer 32

CDC recommends repeating testing 28-36 weeks in: women with previous prenatal diagnosis of STD or those with continued risk factors
CDC recommends retesting Chlamydia in all women

Question 33

CBC and antibody screening

Answer 33

Repeat in third trimester for anemia screening
Repeat antibody screening in unsensitized RH neg women although data shows that repeat testing may not be necessary if the initial screen was negative. Administer Rhogam as indicated

Question 34

Group B beta-hemolytic streptococcus screening

Answer 34

All pregnant women should be screened 35-37 weeks gestation with samples both lower vagina and rectum

Question 35

Components of second and third trimester ultrasound

Answer 35

Presence or absence of fetal cardiac activity
cardiac rate and rhythm
Fetal number
Fetal presentation
Assessment of amniotic fluid volume
Placental appearance and location
Fetal biometry (biparietal diameter and/or head circumference, femoral length, abdominal diameter and/or circumference)
Evaluation of the uterus, cervix, adnexa when clinically appropriate
Fetal anatomic survey

Question 36

US in third trimester recommendations

Answer 36

to assess intrauterine growth restriction (IUGR)

Routine screening in third trimester is not recommended to screen for IUGR in low risk women.

Question 37

Biophysical Profile-to assess fetal well being

Answer 37

Fetal movement
Fetal tone
Fetal breathing
Amniotic fluid volume
Results of nonstress testing(not always performed)