OB Final Study Guide
Chapter 16 and 32:
Fundal height measurements in relation to gestational weeks
o 12-14 weeks: above the symphysis pubis
o 20-22: level of umbilicus
o Xyphoid process at term
o 38-40: fundal height decreases as the fetus begins to descend into pelvis
(lightening) in preparation for birth.
Lightening: 2 weeks before onset of labor in nullipara and at the start of
labor in multipara.
Be able to identify the fetal positions based on a picture (LOA, ROA, ROP, LSA, RSA,
shoulder presentation, and the different types of breech presentation)
o SEE FETAL PRESENTATION WOKRSHEET ON RESOURCES
Know the following terms
o Bloody show: mucus plug/vaginal discharge (blood-tinged cervical mucus). There
is very little bloody show in the beginning, but amount increased with
effacement and dilation of cervix.
o Rupture of membranes: gush/leakage of fluid (nitrazine test: turns blue if positive
for amniotic fluid)
o Effacement: shortening and thinning of the cervix during the 1st stage of labor.
cervix starts out long, thick, and firm.
0%=thick
50%= half thicknes/half effeced
100%=cervix completely thinned out
o Dilation: enlargement or widening of the cervical opening and canal that occurs
once labor has begun.
o Station: measure of the degree of descent of the presenting part of the fetus
through the birth canal (0 station= ischial spines)
VBAC
o VBAC is a vaginal birth after a cesarean, it is contraindicated in women who had a
classical incision d/t risk of uterine rupture.
Amniotomy
o Artificial rupture of membranes to induce labor when the condition of the cervix
is ripe or to augment labor if progress begins to slow.
o It is performed by inserting an amnihook or other sharp instrument is inserted
through the vagina and cervix to rupture membranes
o Dr.’s must perform- outside of nursing practice
o Assessment
, FHR- immediately before and after (transient tachycardia common,
bradycardia and variable decels may indicate cord prolapse/compression)
What is the nurse’s priority after the membranes have ruptured? Why?
o Temp should be monitored Q2H after membrane rupture or more frequently if
there are s/s of infection.
Where is the point of maximal intensity (PMI) of FHR located? Where is it located in a
breech presentation compared to a vertex presentation?
o PMI is usually directly over the fetal back.
Vertex: below the mothers umbilicus in either the R or LLQ of the
abdomen.
Breech: above the mothers umbilicus
What is oxytocin, misoprostol, and dinoprostone? What are the indications (why do
we give these medications)?
o Oxytocin: may be used either to induce labor or to augment labor that is
progressing slowly because of inadequate uterine contractions
Can cause uterine tachysystole (more than 5 contractions in 10 mins
averaged over 30 min window)
Goal is to use the lowest dose possible to produce effective contractions
Start at 1mu/min and increase every 30 mins by 1-2mu/min. (takes uterus
3-5 mins to respond)
Maternal complications: placental abruption, uterine rupture, PPH, and
infection.
Fetal complications: hypoxemia and acidemia, late decelerations and
minimal or absent variability.
o Misoprostol (cytotec): ripens the cervix (softening that results in effacement and
dilation). It is in a tablet form that is inserted intravaginal into the posterior
vaginal fornix without lubricant.
Initial dose is 25 mcg and it can be repeated every 4 hours or until an
effective contraction pattern is established (3 contractions or more in 10
minutes), the cervix ripens (Bishop score of 8 or greater), or significant
adverse effects occur.
SE: N/V/D, fever, uterine tachysystole, and fetal passage of meconium.
o Dinoprostone (Cervidil/Prepidil): only FDA approved medication for cervical
ripening or labor induction. It is used when the Bishop score is 4 or less to ripen
the cervix before the administration of oxytocin.
not recommended for women who have had c-section or other uterine
sx.
Cervidil: 10 mg that releases slowly over 12 hours or it may be removed
earlier for the onset of active labor or if uterine tachysystole or abnormal
FHR occurs.
, Prepidil: dose is 0.5 mg and is administered through a catheter inserted in
the vagina just below the internal cervical os. Dose may be repeated
every 6 hours for a max of 3 doses in a 24 hour period.
SE: headache, N/V/D, fever, hypotension, uterine tachysystole with or without
FHR and pattern, or fetal passage of meconium.
GBS Positive
o All women should be tested at 35-37 wks using rectovaginal culture
o IV abx during labor for women who test positive.
If a women starts going into labor before the woman has been tested for GBS, IV
abx should still be given for prophylaxis.
Usually Penicillin or Ampicillin is used.
Preeclampsia/Eclampsia/HELLP
o Preeclampsia: HTN and proteinuria that develop after 20 wks in a women who
previously had neither condition.
Can also develop for the first time during the PP period.
S/s:
Edema
High BP
Hyperactive reflexes (clonus) at ankle joint
Proteinuria
Severe HA
Epigastric pain/RUQ pain
Visual disturbances
TX: magnesium sulfate (4-6g loading dose; then maintenance dose of 2-3g/hr)
Can cause resp and cardiac arrest if toxicity occurs (give calcium
gluconate)
Nursing interventions:
Watch vital signs, DTR, I&O’s, and LOC
Monitor mag sulfate infusion for complications
Give antihypertensives if BP exceeds 160/110
Continuous FHR monitoring/contractions; assess for s/s of placental
abruption
Bed rest with side rails up in quiet, dark room
Corticosteroids/antihypertensives
o Eclampsia: onset of seizure activity or coma in a woman with preeclampsia who has no
history of preexisting pathology that can result in seizure activity.
s/s:
persistent HA/blurred vision
severe epigastric pain
seizures
TX/Nursing interventions:
Ensure patent airway and client safety (seizure precautions)
Call for help but remain at bedside
Side rails raised and padded
, Suction airway secretions and administer 10L of O2 by face mask
Admin mag. Sulfate
After woman is stabilized, uterine activity, cervical status, and fetal
status should be assessed.
Method of birth is then decided based on stability of mom and baby
o HELLP:
Hemolysis
Elevated Liver enzymes
Low platelet count
Hx of malaise
Flu-like symtoms
Epigastric/RUQ pain
Symptoms worse at night then improve during daytime
Prolapsed Cord
o Occurs when cord lies below the presenting part of the fetus
o May occur with an amniotomy if the presenting part is high.
o Common causes:
Long cord (longer than 100 cm)
Malpresentation (breech)
Transverse lie
Unengaged presenting part
o TX: prompt recognition, emergency c-section, keep hand in vagina to keep pressure off
the cord.
HCG and Prolactin
o Prolactin is produced during breast-feeding to help with milk let-down.
o HCG can be detected in the maternal serum 8-10 days after conception, shortly after
implantation.
Placental Abruption
o Detachment of part or all of the placenta from the uterus.
o Highly suspected in a woman who experiences sudden onset of intense, localized,
uterine pain w/ or w/o vaginal bleeding.
Abdominal pain/tenderness
Contractions
Fundal height may increase indicating concealed bleeding
Abnormal FHR
Coagulopathy (abnormal clotting studies)
o Management: immediate birth is the management of choice if fetus is term gestation or
the bleeding is moderate to severe and the mother or fetus is in jeopardy.
Placenta Previa
o Placenta is implanted in the lower uterine segment such that it completely or partially
covers the cervix or is close enough to the cervix to cause bleeding.
o Risk factors: previous cesarean birth, advanced maternal age (35-40), multiparity, hx of
prior suction curettage, and smoking.
Chapter 16 and 32:
Fundal height measurements in relation to gestational weeks
o 12-14 weeks: above the symphysis pubis
o 20-22: level of umbilicus
o Xyphoid process at term
o 38-40: fundal height decreases as the fetus begins to descend into pelvis
(lightening) in preparation for birth.
Lightening: 2 weeks before onset of labor in nullipara and at the start of
labor in multipara.
Be able to identify the fetal positions based on a picture (LOA, ROA, ROP, LSA, RSA,
shoulder presentation, and the different types of breech presentation)
o SEE FETAL PRESENTATION WOKRSHEET ON RESOURCES
Know the following terms
o Bloody show: mucus plug/vaginal discharge (blood-tinged cervical mucus). There
is very little bloody show in the beginning, but amount increased with
effacement and dilation of cervix.
o Rupture of membranes: gush/leakage of fluid (nitrazine test: turns blue if positive
for amniotic fluid)
o Effacement: shortening and thinning of the cervix during the 1st stage of labor.
cervix starts out long, thick, and firm.
0%=thick
50%= half thicknes/half effeced
100%=cervix completely thinned out
o Dilation: enlargement or widening of the cervical opening and canal that occurs
once labor has begun.
o Station: measure of the degree of descent of the presenting part of the fetus
through the birth canal (0 station= ischial spines)
VBAC
o VBAC is a vaginal birth after a cesarean, it is contraindicated in women who had a
classical incision d/t risk of uterine rupture.
Amniotomy
o Artificial rupture of membranes to induce labor when the condition of the cervix
is ripe or to augment labor if progress begins to slow.
o It is performed by inserting an amnihook or other sharp instrument is inserted
through the vagina and cervix to rupture membranes
o Dr.’s must perform- outside of nursing practice
o Assessment
, FHR- immediately before and after (transient tachycardia common,
bradycardia and variable decels may indicate cord prolapse/compression)
What is the nurse’s priority after the membranes have ruptured? Why?
o Temp should be monitored Q2H after membrane rupture or more frequently if
there are s/s of infection.
Where is the point of maximal intensity (PMI) of FHR located? Where is it located in a
breech presentation compared to a vertex presentation?
o PMI is usually directly over the fetal back.
Vertex: below the mothers umbilicus in either the R or LLQ of the
abdomen.
Breech: above the mothers umbilicus
What is oxytocin, misoprostol, and dinoprostone? What are the indications (why do
we give these medications)?
o Oxytocin: may be used either to induce labor or to augment labor that is
progressing slowly because of inadequate uterine contractions
Can cause uterine tachysystole (more than 5 contractions in 10 mins
averaged over 30 min window)
Goal is to use the lowest dose possible to produce effective contractions
Start at 1mu/min and increase every 30 mins by 1-2mu/min. (takes uterus
3-5 mins to respond)
Maternal complications: placental abruption, uterine rupture, PPH, and
infection.
Fetal complications: hypoxemia and acidemia, late decelerations and
minimal or absent variability.
o Misoprostol (cytotec): ripens the cervix (softening that results in effacement and
dilation). It is in a tablet form that is inserted intravaginal into the posterior
vaginal fornix without lubricant.
Initial dose is 25 mcg and it can be repeated every 4 hours or until an
effective contraction pattern is established (3 contractions or more in 10
minutes), the cervix ripens (Bishop score of 8 or greater), or significant
adverse effects occur.
SE: N/V/D, fever, uterine tachysystole, and fetal passage of meconium.
o Dinoprostone (Cervidil/Prepidil): only FDA approved medication for cervical
ripening or labor induction. It is used when the Bishop score is 4 or less to ripen
the cervix before the administration of oxytocin.
not recommended for women who have had c-section or other uterine
sx.
Cervidil: 10 mg that releases slowly over 12 hours or it may be removed
earlier for the onset of active labor or if uterine tachysystole or abnormal
FHR occurs.
, Prepidil: dose is 0.5 mg and is administered through a catheter inserted in
the vagina just below the internal cervical os. Dose may be repeated
every 6 hours for a max of 3 doses in a 24 hour period.
SE: headache, N/V/D, fever, hypotension, uterine tachysystole with or without
FHR and pattern, or fetal passage of meconium.
GBS Positive
o All women should be tested at 35-37 wks using rectovaginal culture
o IV abx during labor for women who test positive.
If a women starts going into labor before the woman has been tested for GBS, IV
abx should still be given for prophylaxis.
Usually Penicillin or Ampicillin is used.
Preeclampsia/Eclampsia/HELLP
o Preeclampsia: HTN and proteinuria that develop after 20 wks in a women who
previously had neither condition.
Can also develop for the first time during the PP period.
S/s:
Edema
High BP
Hyperactive reflexes (clonus) at ankle joint
Proteinuria
Severe HA
Epigastric pain/RUQ pain
Visual disturbances
TX: magnesium sulfate (4-6g loading dose; then maintenance dose of 2-3g/hr)
Can cause resp and cardiac arrest if toxicity occurs (give calcium
gluconate)
Nursing interventions:
Watch vital signs, DTR, I&O’s, and LOC
Monitor mag sulfate infusion for complications
Give antihypertensives if BP exceeds 160/110
Continuous FHR monitoring/contractions; assess for s/s of placental
abruption
Bed rest with side rails up in quiet, dark room
Corticosteroids/antihypertensives
o Eclampsia: onset of seizure activity or coma in a woman with preeclampsia who has no
history of preexisting pathology that can result in seizure activity.
s/s:
persistent HA/blurred vision
severe epigastric pain
seizures
TX/Nursing interventions:
Ensure patent airway and client safety (seizure precautions)
Call for help but remain at bedside
Side rails raised and padded
, Suction airway secretions and administer 10L of O2 by face mask
Admin mag. Sulfate
After woman is stabilized, uterine activity, cervical status, and fetal
status should be assessed.
Method of birth is then decided based on stability of mom and baby
o HELLP:
Hemolysis
Elevated Liver enzymes
Low platelet count
Hx of malaise
Flu-like symtoms
Epigastric/RUQ pain
Symptoms worse at night then improve during daytime
Prolapsed Cord
o Occurs when cord lies below the presenting part of the fetus
o May occur with an amniotomy if the presenting part is high.
o Common causes:
Long cord (longer than 100 cm)
Malpresentation (breech)
Transverse lie
Unengaged presenting part
o TX: prompt recognition, emergency c-section, keep hand in vagina to keep pressure off
the cord.
HCG and Prolactin
o Prolactin is produced during breast-feeding to help with milk let-down.
o HCG can be detected in the maternal serum 8-10 days after conception, shortly after
implantation.
Placental Abruption
o Detachment of part or all of the placenta from the uterus.
o Highly suspected in a woman who experiences sudden onset of intense, localized,
uterine pain w/ or w/o vaginal bleeding.
Abdominal pain/tenderness
Contractions
Fundal height may increase indicating concealed bleeding
Abnormal FHR
Coagulopathy (abnormal clotting studies)
o Management: immediate birth is the management of choice if fetus is term gestation or
the bleeding is moderate to severe and the mother or fetus is in jeopardy.
Placenta Previa
o Placenta is implanted in the lower uterine segment such that it completely or partially
covers the cervix or is close enough to the cervix to cause bleeding.
o Risk factors: previous cesarean birth, advanced maternal age (35-40), multiparity, hx of
prior suction curettage, and smoking.
