OB Ch. 6: Antepartal Tests
Assessment for Risk e Biophysical factors
Factors e Psychosocial factors
e Sociodemographic factors
e Environmental factors
Nurse’s Role in e Provide information regarding the test
Antepartal Tests e Provide comfort
e Reassure the woman and her partner
e Provide psychosocial support to woman and her partner
e Document woman’s response and the results of tests
Biophysical e Procedure
Assessments: o An ultrasound examination may be performed either transabdominally or
transvaginally.
Ultrasonography o Transvaginal ultrasound is generally performed in the first trimester for
earlier visualization of the fetus.
o Abdominal ultrasound requires the woman to be in a supine position.
m A full bladder is necessary to elevate the uterus out of the pelvis
for better visualization when performed during the first half of
pregnancy.
m Transmission gel and transducer are placed on the maternal
A0Ddomen
nterpretation
o Ultrasound for gestational age is most accurate when performed before 14
weeks to determine gestational age plus or minus 1 week
Normal findings for the fetus are appropriate gestational age, size, viability,
position, and functional capacities
Normal findings for the placenta are expected size, normal position and
structure, and an adequate amniotic fluid volume
Accurate assessments of gestational age, fetal growth, and detection of
fetal and placental abnormalities
o Noninvasive & Provides information on fetal structures and status
Nursing Actions
o Explain to the woman and her family that ultrasound uses sound waves to
produce an image of the baby.
o Assess for latex allergies with transvaginal ultrasound.
o For transvaginal ultrasound, inform the woman that a sterile sheathed
probe is inserted into the vagina. Inform her that she may feel pressure, but
pain is not usually felt.
Position the patient in a lithotomy position for transvaginal ultrasound
and supine for abdominal ultrasound.
o Be sensitive to cultural and social as well as modesty issues, Provide
emotional support, & Schedule appropriate follow-up.
The 3D and 4D ultrasounds are ordered as needed for further evaluation of possible
fetal anomalies such as facial, cardiac, and skeletal.
The 3D and 4D ultrasounds are most commonly requested by the patient to see a
more lifelike picture of their developing baby in utero.
3D and 4D ultrasounds allow visualization of complex facial movements & features,
‘branching of placental stem vessels, and connection of the umbilical vessels to the
chorionic plate of the placenta
, Umbilical Artery urpose — Assesses placental perfusion
Doppler Flow o This is a noninvasive screening technique that uses advanced ultrasound
o technology to assess resistance to blood flow in the placenta.
o It evaluates the rate and volume of blood flow through the placenta and
‘umbilical cord vessels using ultrasound.
m Increased resistance in the placenta, suggestive of poor
function, results in reduced diastolic blood flow
sed In combination with other diagnostic tests 10 assess fetal status in
intrauterine growth restriction (IUGR) fetuses
e Procedure "
') / o The woman is assisted into a supine position. m . (.s A
’ ‘ o Transmission gel and transducer are placed on the woman'’s a domen
o Images are obtained of blood flow in the umbilical artery.
e Interpretation
o The directed blood flow within the umbilical arteries is calculated using the
L4 difference between systolic and diastolic flow
e
o Umbilical Artery Doppler is considered abnormal if the systolic/diastolic
8\
ratio is above the 95th percentile for gestational age, or the end-diastolic
flow is absent or reversed
+ Ao e UIOT= E
VYRS
GA OUNA
;S\Sfi
o Allows for assessment of placental perfusion
e Nursing Actions
o Explain the procedure to the woman and her family — The Doppler test
AV
‘ evaluates the blood flow through the placenta and umbilical cord vessels
using ultrasound.
[¢] Address questions and concerns, Provide comfort measures, Provide
emotional support, Schedule appropriate follow-up.
Magnetic Resonance e Procedure
Imaging (MRI) — o Tissue, organs, and vascular structures can be evaluated without the need
suspect baby has brain to inject iodinated contrast.
abnormality o The woman is instructed to remove all metallic objects before the test.
o During pregnancy, MRl is used to visualize maternal or fetal structures for
@ detailed imaging when screening tests indicate possible abnormalities.
o o Itis most commonly performed for complex fetal anomalies such as
suspected brain abnormality or to further evaluate abnormal placentation
e Interpretation: by a radiologist
e Advantages
o Provides very detailed images of fetal anatomy
o particularly useful for brain abnormalities and complex abnormalities of the
thorax, gastrointestinal, and genitourinary systems and to evaluate
abnormal placentation.
Nursing Actions
o Nurses are involved in the pre- and post-procedure.
o Explain the procedure to the woman and her family — The MRI is used to
see maternal or fetal structures for detailed pictures.
o Address questions and concerns and provide information and support
(some women may experience claustrophobia or fear of equipment)
Chorionic Villi e Procedure
Sampling (CVS) o CVS is aspiration of a small amount of placental tissue (chorionic villi) for
e 10-12 weeks chromosomal, metabolic, or DNA testing
gestation (1st o Performed as early as 10-12 weeks gestation (1st or 2nd trimester)
or 2nd o Tests for fetal abnormalities caused by genetic disorders (such as CF)
trimester) o Transvaginally and used with ultrasound e ‘
Placental tissue sample biopsy Mm‘n mw
o
e Interpretation
o Invasive = big, long needle — Need RhoGam if mom is Rh Negative
o Results of chromosomal studies are available within 1 week.
m Detailed information is provided on the specific chromosomal
WIWKYANOMA st Fniocenesis
, Chorionic Villi abnormality detected:
Sampling (CVS) Advantages
o 10-12 weeks o The primary advantage of CVS over amniocentesis is that the procedure
gestation (1st can be performed earlier in pregnancy and the viable cells obtained by CVS
or 2nd for analysis allow for shorter specimen processing time (5 to 7 days versus
trimester) 7 to 14 days), so the results are available earlier in pregnancy.
o Can be performed earlier than amniocentesis but is not recommended
V0SNG !
Bleeding (10% of women) ! f E MM‘"
Infection
o Assess fetal and maternal well-being post-procedure.
o Auscultate FHR twice in 30 minutes.
o Instruct the woman to REPORT abdominal pain or cramping, leaking of
fluid, bleeding, fever, or chills to the care provider.
o Review the procedure with the woman and her family — This test obtains
amniotic fluid to test for fetal abnormalities caused by genetic problems.
Amniocentesis Procedure
e Done at 15-20 o Offered between 15 and 20 weeks for genetic testing (Abdominally)
weeks o Amniocentesis is the most common technique used for obtaining fetal cells
for genetic testing. It is a diagnostic procedure in which a needle is inserted
through the maternal abdominal wall into the uterine cavity to obtain
2:1 indicates fetal lung
maturity g yp
assessment of fetal lung maturity, assessment of hemolytic disease,
Positive PG indicates or intrauterine infection and therapy for polyhydramnios, gender
fetal lung maturity
o An amniotic fluid sample is sent to a laboratory for cell growth, and results
An LBC of 50,000/uL or of the chromosomal studies are available within 2 weeks.
greater is highly m Elevated bilirubin levels indicate fetal hemolytic disease.
indicative of fetal lung o Standards do not recommend amniocentesis be done solely to evaluate the
lecithin/sphingomyelin (L/S) ratio or the presence of phosphatidyl glycerol
(PG).
o LIS (lecithin/sphingomyelin) ratio greater than 2:1 indicates fetal lung
maturity.
| L/S ratio < 2:1 indicates fetal lung immaturity in increased risk of
respiratory distress syndrome.
\g o Positive PG (phosphatidyl glycerol ) indicates fetal lung maturity.
o An LBC (lamellar body count) of 50,000/uL or greater is highly indicative
of fetal lung maturity.
Advantages
o Examines fetal chromosomes for genetic disorders "
o i e inati i i pecimens
S
o Trauma to the fetus or placenta
o Preterm labor m
[ Maternal i L ) J
|
O Explain that in the amniocentesis procedure a needle is inserted through
the abdomen into the womb to obtain amniotic fluid for testing.
Explain that discomfort will be minimized during needle aspiration with a
o
local anesthetic.
Explain that a full bladder may be required for ultrasound visualization
if the woman is less than 20 weeks’ gestation.
o Assess fetal and maternal well-being post-procedure, monitoring and
evaluating the FHR.
Instruct the woman to REPORT abdominal pain or cramping, leaking
AONMO0= POSt PIC@ MSATP
of fluid, bleeding, decreased fetal movement, fever, or chills to the
, Amniocentesis
A
] NI0:nie -
care provider.
’ o ; Z
'
e Done at 15-20 Instruct the woman not to lift anflhing heafl for 2 daxs.
weeks Administer RhoGAM to Rh-negative women post-procedure as per
order to prevent antibody formation in the Rh-negative woman.
Percutaneous
Umbilical Blood PUBS is the removal of fetal blood from the umbilical cord. The blood
Sampling (PUBS) is used to test for metabolic and hematological disorders, fetal
e After 18 weeks infection. and fetal karvotvoina
(2nd trimester, 'sually used after ultrasound has detected an anomaly
) | o Usually performed after 18 weeks’ gestation (2nd Trimester)
\ o A needle is inserted into the umbilical vein at or near the placental origin
and a small sample of fetal blood is aspirated
o Ultrasound is used to guide the needle.
Interpretation \
o Results are usually available within 48 hours.
Advantages
o Direct examination of fetal blood sample for fetal anomalies
Risks
o ll Complications are similar to those for amniocentesis and include cord
vessel bleeding or hematomas, maternal-fetal hemorrhage, fetal
brad cardia, and risk for infection.
Explaln the procedure to the woman and her family — During PUBS, fetal
blood is removed from the umbilical cord.
Position the client in a lateral or wedged position to avoid supine
hypotension during fetal monitoring tests.
Have terbutaline ready as ordered in case uterine contractions (UCs)
€]
occur during the procedure.
o Assess fetal well-being post-procedure for 1 to 2 hours via external
fetal monitoring.
Educate the patient on how to count fetal movements for when she goes
[¢]
home.
Alpha-fetoprotein Procedure
(AFP)/a1-Fetoprotein/ o AFP is a glycoprotein produced in the fetal liver, gastrointestinal tract, and
Maternal Serum yolk sac in early gestation.
Alpha-Fetoprotein Assessing for the levels of AFP in the maternal blood is a screening
(MSAFP) tool for certain developmental defects in the fetus, such as fetal NTDs
e 15to 20 weeks and ventral abdominal wall defects
AYP
gestation m Doesn't diagnose if something is wrong (instead will need
further testing — amniocentesis)
Increased levels are associated with defects such as NTDs,
anencephaly, omphalocele, and gastroschisis (Gl defects).
Decreased levels are associated with trisomy 21 (Down syndrome).
o Between 80% and 85% of all open NTDs and open abdominal wall defects
and 90% of anencephalies can be detected early in pregnancy
o The high false-positive rate (meaning the test results indicate an
abnormality in a normal fetus) can result in increased anxiety for a woman
and her family as they wait for the results of additional testing
Nursing Actions
o Educate the woman about the screening test — The AFP test is a maternal
blood test that evaluates the levels of AFP in the maternal blood to screen
for certain fetal abnormalities.
o Support the woman and her family, particularly if results are abnormal.
o Provide information on support groups if an NTD occurs.
Afi’ S DOWN = DOWN SYNNDROME
Assessment for Risk e Biophysical factors
Factors e Psychosocial factors
e Sociodemographic factors
e Environmental factors
Nurse’s Role in e Provide information regarding the test
Antepartal Tests e Provide comfort
e Reassure the woman and her partner
e Provide psychosocial support to woman and her partner
e Document woman’s response and the results of tests
Biophysical e Procedure
Assessments: o An ultrasound examination may be performed either transabdominally or
transvaginally.
Ultrasonography o Transvaginal ultrasound is generally performed in the first trimester for
earlier visualization of the fetus.
o Abdominal ultrasound requires the woman to be in a supine position.
m A full bladder is necessary to elevate the uterus out of the pelvis
for better visualization when performed during the first half of
pregnancy.
m Transmission gel and transducer are placed on the maternal
A0Ddomen
nterpretation
o Ultrasound for gestational age is most accurate when performed before 14
weeks to determine gestational age plus or minus 1 week
Normal findings for the fetus are appropriate gestational age, size, viability,
position, and functional capacities
Normal findings for the placenta are expected size, normal position and
structure, and an adequate amniotic fluid volume
Accurate assessments of gestational age, fetal growth, and detection of
fetal and placental abnormalities
o Noninvasive & Provides information on fetal structures and status
Nursing Actions
o Explain to the woman and her family that ultrasound uses sound waves to
produce an image of the baby.
o Assess for latex allergies with transvaginal ultrasound.
o For transvaginal ultrasound, inform the woman that a sterile sheathed
probe is inserted into the vagina. Inform her that she may feel pressure, but
pain is not usually felt.
Position the patient in a lithotomy position for transvaginal ultrasound
and supine for abdominal ultrasound.
o Be sensitive to cultural and social as well as modesty issues, Provide
emotional support, & Schedule appropriate follow-up.
The 3D and 4D ultrasounds are ordered as needed for further evaluation of possible
fetal anomalies such as facial, cardiac, and skeletal.
The 3D and 4D ultrasounds are most commonly requested by the patient to see a
more lifelike picture of their developing baby in utero.
3D and 4D ultrasounds allow visualization of complex facial movements & features,
‘branching of placental stem vessels, and connection of the umbilical vessels to the
chorionic plate of the placenta
, Umbilical Artery urpose — Assesses placental perfusion
Doppler Flow o This is a noninvasive screening technique that uses advanced ultrasound
o technology to assess resistance to blood flow in the placenta.
o It evaluates the rate and volume of blood flow through the placenta and
‘umbilical cord vessels using ultrasound.
m Increased resistance in the placenta, suggestive of poor
function, results in reduced diastolic blood flow
sed In combination with other diagnostic tests 10 assess fetal status in
intrauterine growth restriction (IUGR) fetuses
e Procedure "
') / o The woman is assisted into a supine position. m . (.s A
’ ‘ o Transmission gel and transducer are placed on the woman'’s a domen
o Images are obtained of blood flow in the umbilical artery.
e Interpretation
o The directed blood flow within the umbilical arteries is calculated using the
L4 difference between systolic and diastolic flow
e
o Umbilical Artery Doppler is considered abnormal if the systolic/diastolic
8\
ratio is above the 95th percentile for gestational age, or the end-diastolic
flow is absent or reversed
+ Ao e UIOT= E
VYRS
GA OUNA
;S\Sfi
o Allows for assessment of placental perfusion
e Nursing Actions
o Explain the procedure to the woman and her family — The Doppler test
AV
‘ evaluates the blood flow through the placenta and umbilical cord vessels
using ultrasound.
[¢] Address questions and concerns, Provide comfort measures, Provide
emotional support, Schedule appropriate follow-up.
Magnetic Resonance e Procedure
Imaging (MRI) — o Tissue, organs, and vascular structures can be evaluated without the need
suspect baby has brain to inject iodinated contrast.
abnormality o The woman is instructed to remove all metallic objects before the test.
o During pregnancy, MRl is used to visualize maternal or fetal structures for
@ detailed imaging when screening tests indicate possible abnormalities.
o o Itis most commonly performed for complex fetal anomalies such as
suspected brain abnormality or to further evaluate abnormal placentation
e Interpretation: by a radiologist
e Advantages
o Provides very detailed images of fetal anatomy
o particularly useful for brain abnormalities and complex abnormalities of the
thorax, gastrointestinal, and genitourinary systems and to evaluate
abnormal placentation.
Nursing Actions
o Nurses are involved in the pre- and post-procedure.
o Explain the procedure to the woman and her family — The MRI is used to
see maternal or fetal structures for detailed pictures.
o Address questions and concerns and provide information and support
(some women may experience claustrophobia or fear of equipment)
Chorionic Villi e Procedure
Sampling (CVS) o CVS is aspiration of a small amount of placental tissue (chorionic villi) for
e 10-12 weeks chromosomal, metabolic, or DNA testing
gestation (1st o Performed as early as 10-12 weeks gestation (1st or 2nd trimester)
or 2nd o Tests for fetal abnormalities caused by genetic disorders (such as CF)
trimester) o Transvaginally and used with ultrasound e ‘
Placental tissue sample biopsy Mm‘n mw
o
e Interpretation
o Invasive = big, long needle — Need RhoGam if mom is Rh Negative
o Results of chromosomal studies are available within 1 week.
m Detailed information is provided on the specific chromosomal
WIWKYANOMA st Fniocenesis
, Chorionic Villi abnormality detected:
Sampling (CVS) Advantages
o 10-12 weeks o The primary advantage of CVS over amniocentesis is that the procedure
gestation (1st can be performed earlier in pregnancy and the viable cells obtained by CVS
or 2nd for analysis allow for shorter specimen processing time (5 to 7 days versus
trimester) 7 to 14 days), so the results are available earlier in pregnancy.
o Can be performed earlier than amniocentesis but is not recommended
V0SNG !
Bleeding (10% of women) ! f E MM‘"
Infection
o Assess fetal and maternal well-being post-procedure.
o Auscultate FHR twice in 30 minutes.
o Instruct the woman to REPORT abdominal pain or cramping, leaking of
fluid, bleeding, fever, or chills to the care provider.
o Review the procedure with the woman and her family — This test obtains
amniotic fluid to test for fetal abnormalities caused by genetic problems.
Amniocentesis Procedure
e Done at 15-20 o Offered between 15 and 20 weeks for genetic testing (Abdominally)
weeks o Amniocentesis is the most common technique used for obtaining fetal cells
for genetic testing. It is a diagnostic procedure in which a needle is inserted
through the maternal abdominal wall into the uterine cavity to obtain
2:1 indicates fetal lung
maturity g yp
assessment of fetal lung maturity, assessment of hemolytic disease,
Positive PG indicates or intrauterine infection and therapy for polyhydramnios, gender
fetal lung maturity
o An amniotic fluid sample is sent to a laboratory for cell growth, and results
An LBC of 50,000/uL or of the chromosomal studies are available within 2 weeks.
greater is highly m Elevated bilirubin levels indicate fetal hemolytic disease.
indicative of fetal lung o Standards do not recommend amniocentesis be done solely to evaluate the
lecithin/sphingomyelin (L/S) ratio or the presence of phosphatidyl glycerol
(PG).
o LIS (lecithin/sphingomyelin) ratio greater than 2:1 indicates fetal lung
maturity.
| L/S ratio < 2:1 indicates fetal lung immaturity in increased risk of
respiratory distress syndrome.
\g o Positive PG (phosphatidyl glycerol ) indicates fetal lung maturity.
o An LBC (lamellar body count) of 50,000/uL or greater is highly indicative
of fetal lung maturity.
Advantages
o Examines fetal chromosomes for genetic disorders "
o i e inati i i pecimens
S
o Trauma to the fetus or placenta
o Preterm labor m
[ Maternal i L ) J
|
O Explain that in the amniocentesis procedure a needle is inserted through
the abdomen into the womb to obtain amniotic fluid for testing.
Explain that discomfort will be minimized during needle aspiration with a
o
local anesthetic.
Explain that a full bladder may be required for ultrasound visualization
if the woman is less than 20 weeks’ gestation.
o Assess fetal and maternal well-being post-procedure, monitoring and
evaluating the FHR.
Instruct the woman to REPORT abdominal pain or cramping, leaking
AONMO0= POSt PIC@ MSATP
of fluid, bleeding, decreased fetal movement, fever, or chills to the
, Amniocentesis
A
] NI0:nie -
care provider.
’ o ; Z
'
e Done at 15-20 Instruct the woman not to lift anflhing heafl for 2 daxs.
weeks Administer RhoGAM to Rh-negative women post-procedure as per
order to prevent antibody formation in the Rh-negative woman.
Percutaneous
Umbilical Blood PUBS is the removal of fetal blood from the umbilical cord. The blood
Sampling (PUBS) is used to test for metabolic and hematological disorders, fetal
e After 18 weeks infection. and fetal karvotvoina
(2nd trimester, 'sually used after ultrasound has detected an anomaly
) | o Usually performed after 18 weeks’ gestation (2nd Trimester)
\ o A needle is inserted into the umbilical vein at or near the placental origin
and a small sample of fetal blood is aspirated
o Ultrasound is used to guide the needle.
Interpretation \
o Results are usually available within 48 hours.
Advantages
o Direct examination of fetal blood sample for fetal anomalies
Risks
o ll Complications are similar to those for amniocentesis and include cord
vessel bleeding or hematomas, maternal-fetal hemorrhage, fetal
brad cardia, and risk for infection.
Explaln the procedure to the woman and her family — During PUBS, fetal
blood is removed from the umbilical cord.
Position the client in a lateral or wedged position to avoid supine
hypotension during fetal monitoring tests.
Have terbutaline ready as ordered in case uterine contractions (UCs)
€]
occur during the procedure.
o Assess fetal well-being post-procedure for 1 to 2 hours via external
fetal monitoring.
Educate the patient on how to count fetal movements for when she goes
[¢]
home.
Alpha-fetoprotein Procedure
(AFP)/a1-Fetoprotein/ o AFP is a glycoprotein produced in the fetal liver, gastrointestinal tract, and
Maternal Serum yolk sac in early gestation.
Alpha-Fetoprotein Assessing for the levels of AFP in the maternal blood is a screening
(MSAFP) tool for certain developmental defects in the fetus, such as fetal NTDs
e 15to 20 weeks and ventral abdominal wall defects
AYP
gestation m Doesn't diagnose if something is wrong (instead will need
further testing — amniocentesis)
Increased levels are associated with defects such as NTDs,
anencephaly, omphalocele, and gastroschisis (Gl defects).
Decreased levels are associated with trisomy 21 (Down syndrome).
o Between 80% and 85% of all open NTDs and open abdominal wall defects
and 90% of anencephalies can be detected early in pregnancy
o The high false-positive rate (meaning the test results indicate an
abnormality in a normal fetus) can result in increased anxiety for a woman
and her family as they wait for the results of additional testing
Nursing Actions
o Educate the woman about the screening test — The AFP test is a maternal
blood test that evaluates the levels of AFP in the maternal blood to screen
for certain fetal abnormalities.
o Support the woman and her family, particularly if results are abnormal.
o Provide information on support groups if an NTD occurs.
Afi’ S DOWN = DOWN SYNNDROME
