Obstetric Flashcards
At what level of hCG is gestational sac typically visible on sonography
1,500 to 2,000 mIU/mL
How many weeks is gestational sac typically visible
4-5 weeks
How many weeks can flow on color flow Doppler be seen
4 weeks
How many weeks can heart beat be picked up for embryo
5-6 weeks, but listen in office after 9-10 weeks
When is gestational age most accurate for dating when measuring Crown-Rump length
8 and 13 weeks
Miscarriage Treatment Options
Surgical - D&C - Manual vacuum aspiration Medical - Misoprostol (off-label use) Expectant
Most successful management for incomplete miscarriage
Expectant and medical management
Most successful management for missed abortion
Medical and surgical more effective than expectant management
Advantages and disadvantages of women managed expectantly for miscarriages
Have more outpatient visits than those treated with misoprostol
Advantages and disadvantages of women managed with misoprostol
have more bleeding but less pain than those treated surgically
Disadvantages of women managed with surgery for miscarriages
more trauma and infectious
Different ways of taking misoprostol for miscarriages and why the route can effect decision making
Fewer gastrointestinal adverse effects when given vaginally or buccal route than when given orally
Gold standard for diagnosis of ectopic pregnancy
Laparoscopy
Lab diagnosis of ectopic pregnancy
Failure of beta hCG to rise appropriately (53% in 48 hours)
No gestational sac + beta hCG >3,000 to 3,510 mIU/mL highly suggestive
Ectopic Pregnancy Treatments
Surgical salpingectomy or salpingostomy by
- Open laparotomy
- Laparoscopy
Medical
- Methotrexate
Expectant - wait for spontaneous resolution
Mainstay of treatment for ectopic pregnancy
Surgical management
Advantages of methotrexate for ectopic pregnancy
Safe, effective, and less costly than surgery
Equal or better fertility preservation
Findings diagnostic of pregnancy Failure
Crown-rump length of >7 mm and no heartbeat
Mean sac diameter of >25 mm and no embryo
Absence of embryo with heartbeat >2 wk after a scan that showed a gestational sac without a yolk sac
Absence of embryo with heartbeat > 11 days after a scan that showed a gestational sac with a yolk sac
Criteria for medical management of ectopic pregnancy
- Stable vital signs and low level of symptomatology
- No medical contraindications
- Unruptured ectopic pregnancy
- Absence of embryonic cardiac activity
- Ectopic mass <4 cm
- Starting hCG levels <5,000 - 10,000 mIU/mL
Medical contraindications for methotrexate
Abnormal liver enzymes, CBC, or platelet count
Criteria for expectant management of ectopic pregnancy
- Minimal pain or bleeding
- Patient reliable for follow-up
- No evidence for tubal rupture
- Starting hCG level <1,000 mIU/mL and decreasing
- Ectopic or adnexal mass < 3 cm, or not detected
- No embryonic heartbeat
What are the starting hCG levels for medical management of ectopic pregnancy
<5,000 - 10,000 mIU/mL
What are the starting hCG levels for expectant management of ectopic pregnancy
<1,000 mIU/mL and decreasing
What is criteria for ectopic or adnexal mass for expectant management
<3 cm, or not detected
What is the criteria for ectopic mass for medical management (methotrexate)
Ectopic mass <4 cm
Indications for surgical management of ectopic pregnancy
- Unstable vital signs or signs of hemoperitoneum
- Uncertain diagnosis
- Advanced ectopic pregnancy (elevated hCG levels, large mass, cardiac activity)
- Unreliable follow-up
- Contraindication to observation or methotrexate
What is considered an advanced ectopic pregnancy
elevated hCG levels, large mass, and cardiac activity
Definition of chronic hypertension before in pregnancy
- Blood pressure is elevated >/= 140/90 prior to 20 weeks gestation
- No proteinuria (unless pre-existing)
- BP remains elevated beyond 12 weeks postpartum
Gestational hypertension
- Non-proteinuric HTN after 20 weeks gestation
Medication prevention of preeclampsia
Aspirin has some benefit, but is modest with a high number needed to treat for low-risk women
Suggested dose of Aspirin for high risk patient of preeclampsia
60-81 mg
Two main diagnostic criteria for preeclampsia
New onset HTN after 20 weeks with proteinuria
Hypertension numbers for preeclampsia (HTN after 20 weeks with proteinuria)
- BP >140/90 two times, taken 4 hours apart
- BP >160/110 mm Hg once
How is proteinuria defined in the diagnosis of preeclampsia
- 24 hour protein >/= 300 mg
- Protein/creatinine ratio of >/= 0.3
- Timed urine protein level extrapolated out to 24 hour value
- Urine dip +1 or more (only if other methods not available)
- Proteinuria is NOT required if the patient has new onset HTN with specified findings
How can you diagnosis preeclampsia without proteinuria
- Platelets <100,000/uL
- Creatinine >1.1 mg/dL or doubled from baseline
- Transaminases twice the normal levels
- Pulmonary edema
- Cerebral or visual symptoms
- Blood pressure >/=160/110
Diagnostic criteria for severe preeclampsia with severe features
- Blood pressure equal to or exceeding 160 mm Hg systolic of 110 mm Hg diastolic on at least two occasions four hours apart
- Any of the following signs and symptoms
- Serum creatinine >1.1 mg/dL or doubled baseling
- Cerebral or visual disturbances
- Pulmonary edema
- Transaminases 2x normal, RUQ pain or epigastric pain
- Thrombocytopenia (100,000/ml)
Management (including when to deliver) of preeclampsia without severe features
- Expectant management before 37 weeks
- Monitor labs
- Antepartum surveillance
What labs are to be monitored for patients with preeclampsia without severe features
- Baseline CBC, transminases, creatinine, LDH, and uric acid
- Weekly labs
- CBC, transaminases (AST, ALT)
- No need to follow urine protein
Management preeclampsia with severe features and HELLP
- Admit to hospital
- Treatment goals
- Prevent seizures
- Control BP to prevent cerebral hemorrhage
- Expedite delivery, balancing maternal conditions and fetal maturity
Preferred anticonvulsant for preeclampsia with severe features
Magnesium Sulfate
Benefits of Magnesium Sulfate for blood pressure control for preeclampsia with severe features
No significant effect on BP
Decreases risk of placental abruption
Prevents seizures
Check magnesium levels under what circumstances (treating preeclampsia with severe features)
Urine output <30mL/hour
Elevated serum creatinine
Symptoms of MgSO4 toxicity
- Loss of patellar reflexes
Antidote for MgSO4
Calcium gluconate
Symptoms of Magnesium toxicity
Order of increase in dosage
- Loss of patellar reflex
- Somnolence
- Respiratory depression
- Paralysis
- Cardiac arrest
Medications used to treat hypertension in severe preeclampsia
IV labetalol or hydralazine
Diagnosis of eclampsia
Onset of seizures in a patient with preeclampsia
Diagnosis of HELLP Syndrome
Preeclampsia with severe features
Hemolysis
Elevated Liver enzymes
Low Platelets
How is hemolysis diagnosed in HELLP syndrome
Abnormal peripheral smear
LDH elevated
By how much are liver enzymes elevated to diagnose HELLP syndrome
Transaminases >/= twice the normal
Platelet count in HELLP syndrome
<100,000/uL
What should be monitored in postpartum preeclampsia
Blood pressure and urine output
When is a mother at highest risk for seizures in postpartum preeclampsia
24 hours after birth
When does acute fatty liver of pregnancy occur during pregnancy
Third trimester
Symptoms of acute fatty liver of pregnancy
Vomiting, abdominal pain, anorexia, jaundice
Progression of acute fatty liver of pregnancy if not treated
May progress to liver failure, ascites, renal failure, encephalopathy, or death
How to diagnosis acute fatty liver of pregnancy
- Hypoglycemia
- AST elevated, but usually <500 IU/L
- Bilirubin elevated, but usually < 5 mg/dL
- PT and PTT prolonged, fibrinogen decreased
Peripartum Cardiomyopathy timing
Heart failure developing in the last trimester or within 5 months after delivery
Presentation of peripartum cardiomyopathy
dyspnea, fatigue, edema
Medication to avoid in peripartum cardiomyopathy
ACE inhibitors and excess diuresis
Leading cause of maternal mortality in developed countries
Venous Thromboembolism (DVT and PE)
Most common body part for DVT in pregnant women
88% in left leg with unilateral leg pain
Diagnostic criteria for DVT in pregnant women
LEFt Criteria
- Left leg symptoms
- Edema (leg circumference discrepancy of >/= 2)
First trimester at the time symptoms present
DVT in pregnancy occurs in 12% of women with at least one of LEFt criteria
0% occurrence with none
Anticoagulation options in pregnancy in PE
LMWH is treatment of choice in PE (Enoxaparin)
Anticoagulation options in pregnancy in VTE and when is it stopped
LMWH and usually continue for 6 week postpartum
When are anticoagulation discontinued for cesarean or labor
24 hours prior to scheduled inductions and cesarean deliveries
At the onset of labor
High suspicion in a pregnant women of PE with abnormal Xray, what is next step
Computed tomographic pulmonary angiogram (CTPA)
What are the most common causes of life threatening bleeding in late pregnancy
Placenta previa
placental abruption
uterine scar disruption
ruptured vasa previa
Classic presentation of placenta previa
Painless bleeding
- Late second or third trimester
- Provoked by intercourse
- May be accompanied by preterm contraction
What can you suspect in a pregnant women with persistent malpresentation in late third trimester
Placenta previa
Next step for patient with placenta previa seen on transabdominal ultrasound
should perform a transvaginal scan
How to counsel patient with placenta previa and no bleeding
No intercourse or tampons in the third trimester or digital examinations
When is ultrasound follow-up for patient with placenta previa
32 weeks to see if resolved
36 weeks can help determine mode of delivery
In placenta previa, the need for emergency cesarean delivery increase with
- Three or more episodes of antepartum bleeding
- Initial episode of bleeding occurring at <29 weeks
- Shortened cervical length on serial ultrasounds
For known low-lying placenta or marginal previa with no bleeding, from performed ultrasound at 36 weeks, when can vaginal delivery still be attempted
- If placenta is located >/= 2 cm from internal os
- If 1-2 cm from os, may attempt vaginal delivery in setting with immediate surgical backup
Risk factor for placental abruption
- Hypertensive disorders
- Abdominal trauma
- Tobacco, cocaine, amphetamines (stimulates)-Thrombophilia’s
- Chorioamnionitis
- Oligohydramnios with PROM
- History of abruption
Clinical presentation for placental abruption
- Abdominal pain (mild to severe), may have back pain
- Vaginal bleeding or bloody amniotic fluid (may be concealed bleeding)
Three key features of ultrasound findings for placental abruption
First remember ultrasound is not very sensitive
- Retroplacental echolucency
- Abnormal thickening of placenta
- Torn edge of placenta
Timing aspect of expeditious operative or vaginal delivery of mother with severe placental abruption
Decision-to-delivery interval >20 minutes increases incidence of fetal mortality or cerebral palsy
What is essential before an operative delivery of mother with coagulopathy with an placental abruption
Administer platelets, fresh frozen plasma before operative delivery
Most common causes (4) of uterine rupture
- Previous cesarean incision (most common)
- Inappropriate oxytocin usage
- Labor induction
- Uterine over-distention
Clinical findings of a uterine rupture
- Sudden deterioration of FHR pattern is the most common initial sign
- Vaginal bleeding
- Pain, sudden onset
- Stair step decrease or cessation of contractions
- Loss of fetal station
Vasa Previa
Fetal vessels run in membranes between cervix and presenting part
Can result in fetal blood loss
Clinical presentation of vasa previa
Can be detected antenatally
- Will be able to palpate vessels during cervical examination
First sign is typically bleeding with membrane rupture
Delivery time for vasa previa
Deliver at 35-36 weeks
If fetal heart tones on not concerning, fast way to test for fetal blood cells for suspected vasa previa
Wright stain
Antenatal progesterone supplementation decreases
the incidence of preterm delivery in high-risk patients
Administration of corticosteroids in women with preterm labor between 23-34 weeks reduces incidence of what
neonatal mortality
respiratory distress syndrome
intraventricular hemorrhage
What reduces respiratory complication when given to women with threatened preterm labor or ruptures of membranes or an indication for planned late preterm delivery between 34 0/7 and 36 6/7
betamethasone (decrease intra-ventricular hemorrhage, 2 doses over 24 hours)
dexamethasone (cheaper, 4 IM doses over 24 hours)
dependent on institution
In a preterm mother what is considered threatened preterm labor
At lest > 2-3 cm dilated
OR
75%-80% effaced with contractions
For PPROM between 34 0/7 and 36/6/7, what is associated with significantly lower rates of respiratory distress, mechanical ventilation, days spent in NICU, and cesarean delivery but significantly higher rates of antepartum or intrapartum hemorrhage, intrapartum fever, use of postpartum antibiotics, and longer hospital stay
Expectant management
What are the advantages of expectant management for PPROM between 34 0/7 and 36 6/7
Significantly lower rates of
- Respiratory distress
- Mechanical ventilation
- Days spent in NICU
- Cesarean delivery
What are the disadvantages of expectant management for PPROM between 34 0/7 and 36 6/7
Significantly higher rates of:
- Antepartum or intrapartum hemorrhage
- Intrapartum fever
- Use of postpartum antibiotics
- Longer hospital stay
Prior preterm labor what is medication and method delivered
17-alpha-hydroxyprogesterone caporate IM
When is 17-alpha-hydroxyprogesterone caporate IM or vaginal progesterone gel or capsule given for preterm delivery
Prior PTD: 17-alpha
No prior PTD, CL <20 mm at <24 weeks
For prevention of preterm delivery management, at what length is cerclage considered
cervical length <25 mm
For Vaginal progesterone for preterm delivery what is the timing (how often and gestation weeks)
Daily from diagnosis and until 36 weeks
What can make a fetal fibronectin test inaccurate
Presences of vaginal bleeding or Within 24 hours - Intercourse - Digital vaginal examination - Endovaginal ultrasound
What does a negative fetal fibronectin mean
NPV >99% for delivery in 7 to 14 days
Tests for determining membrane rupture
Sterile speculum examination
- Pool of fluid in vaginal vault
- Positive nitrazine testing (blue - alkaline)
- Ferning of amniotic fluid
Drugs for Tocolysis
Nifedipine
Terbutaline
Indomethacin
Magnesium sulfate (less common)
Contraindications for nifedipine as a tocolytic
maternal hypotension
Contraindications for terbutaline as a tocalytic
Heart disease
Poorly controlled diabetes
Thyrotoxicosis
Contraindications for indomethacin as a tocalytic
- Contraindicated after 30 weeks due to association with polyhydramnios
- Contraindicated after 32 weeks due to closure of patient ductus arteriosus
Contraindications for magnesium sulfate in pregnant women
Myasthenia gravis
When is vacuum delivery contraindicated (gestational age)
Less than 34 weeks, due to risk of intracranial hemorrhage
First line treatment for Group B strep in pregnancy
Penicillin or ampicillin
Treatment for Group B strep in pregnancy if there is an allergy (can’t use penicillin or ampicillin)
- Cefazolin second-line for PCN allergy (unless allergy was anaphylaxis or urticaria)
- Clindamycin only if severe PCN allergy and culture proven sensitivity to clindamycin and erythromycin
- Vancomycin if unknow sensitivity or resistant to above
Management of rupture of membranes without labor >34 but <37 weeks
GBS prophylaxis if GBS status is unknown
Management of rupture of membranes without labor >/= 37 weeks
Expedite delivery in setting that is able to care for preterm infant
Management of rupture of membranes without labor <34 weeks
- Admit to hospital
- Give antenatal corticosteroids
- Administer ampicillin and erythromycin to prolong latent labor
What is predictive of normal fetal acid-base status
- moderate FHR variability
- FHR accelerations, whether spontaneous or stimulated
Category III fetal monitoring tracing increases the likelihood of…
fetal acidosis
Next thing to ask if Category II fetal heart rate tracing with moderate variability or accelerations
If patient has significant decelerations with >50% of contractions for 1 hours
Next thing to ask if Category II fetal heart rate tracing without moderate variability or accelerations
If patient has significant decelerations with >50% of contractions for 60 minutes
Next step for Category II fetal heart rate tracing with moderate variability and no significant decelerations
Observe
Next question to ask in a Category II fetal heart rate tracing with moderate variability and/or accelerations who is having significant decelerations with >50% of contractions for 1 hour
Latent phase - Cesarean Active phase - Normal labor progress --Yes: Observe --No: Cesarean Second phase - Normal progress? --Yes: observe --No: Cesarean or OVD
Next question to ask in Category II fetal heart rate tracing with no moderate variability or accelerations and has significant decelerations with >50% of contractions for 30 minutes
Cesarean or OVD
Next question to ask in Category II fetal heart rate tracing with no moderate variability or accelerations and without significant decelerations
Observe for 1 hour
- If persistent pattern have cesarean or OVD
- If no persistent pattern manage per algorithm
A period of CEFM on maternity unit admission for low-risk women compared to initiation of structured auscultation at time of admission results in
Increase epidural
Fetal blood scalp testing
Thus not recommended
Benefits of aminoinfussion for umbilical cord compression the presence of decelerations
Reduces:
- FHR decelerations
- Cesarean delivery overall
- Apgar score <7 at 5 min
- low cord arterial pH
- Neonatal hospital stay > 3 days
- Maternal hospital stay greate than 3 days
When should amnioinfusion be considered
When FHR tracing includes recurrent variable FHR decelerations (Category II or Category III)
When is amnioinfusion not indicated for FHR decelerations
Late FHR decelerations
Management of uterine tachysystole in spontaneous labor with a category I FHR tracing
No interventions required
Management of spontaneous labor with uterine tachy systole with Category II or III FHR tracing
Interuterine resuscititative measure –> If no resolution, consider tocolytic
Main goals for intrauterine Resuscitative measure for Category II or Category II tracings
- Improved uteroplacental blood flow
- Reduce uterine activity
- Alleviate/reduce umbilical cord compression
Potential interventions to improve uteroplacental blood flow
- Lateral positiong
- Administer maternal oxygen
- Administer intravenous fluid bolus
- Discontinue or reduce uterine stimulants
- Administer tocolytics drugs
- Correct maternal hypotension
- Modify maternal expulsive (pushing) efforts
Potential interventions to reduce uterine activity
- Lateral positiong
- Administer IV fluid bolus
- Discontinue or reduce uterine stimulants
- Administer tocolytic drugs
Potential interventions to alleviate/reduce umbilical cord compression
- Reposition to where FHR is most improved
- Discontinue uterine stimulants
- Initiate amnioinfussion if variable decelerations recurrent
- Modify maternal expulsive (pushing) efforts
- Check for prolapsed cord
Management of uterine tachysystole in labor induction with category I FHR tracing
Decrease uterotonics
Management of uterine tachysystole with labor induction and Category II or III FHR tracing
- Decrease or stop uterotonic
- Intrauterine resuscitative measure
- If no resolution, consider tocolytic
What may improve fetal oxygenation during labor
When used together:
IV fluid bolus
Lateral positioning
Oxygen
Modifying pushing techniques
Examples of modifying pushing techniques while in labor
- Discontinuation of pushing
- Pushing every 2nd or 3rd contraction
- Pushing with an open glottis
- Pushing for 6-8 second intervals
Continuous external fetal monitoring does not reduce what
- Incidence of cerebral palsy
- Perinatal mortality
Continuous external fetal monitoring reduces what
Neonatal seizures
What procedures are increased due to continuous external fetal monitoring compared to structure intermittent auscultation
Cesarean delivery rates and instrumental vaginal births
Amniotomy
artificial rupture of membranes
What may help prevent labor dystocia, but routine use alone is not recommended during labor
Amniotomy with oxytocin
a woman, typically without formal obstetric training, who is employed to provide guidance and support to a pregnant woman during labor
doula
Why should clinicians support use of a doula during labor
- Help women use less analgesia
- Lower rates of operative vaginal and cesarean delivery
- More satisfied with their childbirth experiences
Why should clinicians use epidural analgesia with care
Prolongation of the second stage of labor
Increase in:
- Maternal fever
- Oxytocin use
- Operative vaginal delivery
Cesarean delivery for labor dystocia should not occur until what
At least 4 hours without cervical change during active stage of labor with adequate contractions
Define second stage arrest for labor
Second stage is 10 cm dilated to birth of baby
No progress (descent or rotation) for:
≥4 hours in nulliparous women with an epidural
≥3 hours in nulliparous women without an epidural
≥3 hours in multiparous women with an epidural
≥2 hours in multiparous women without an epidural
Cervix dilation for active labor
6 cm
Why should cesarean delivery for dystocia not be done if patient is less than 6 cm
Active labor does not start until 6 cm
When should clinicians allow slower labor progress throughout all stages of labor
Obese women
When should clinicians allow slower labor progress in latent labor
In women undergoing induction compared to spontaneous labor
Latent labor definition
The latent phase of labor begins with maternal perception of painful regular contractions and ends when the rate of dilation begins to accelerate
Breech mneumonic for birth
CAREFUL
- Check dilation, check presentation, cord
- Await umbilicus
- Rotate for arms
- Enter for the Mauriceau-Smellie-Veit (MSV) maneuver (suprapubic pressure and
- -Flex head (back - fingers on maxilla) UP (sacrum anterior)
- Lift baby onto mother
Medication that increase the likelihood of successful external cephalic version
Betamimetics (eg, terbutaline), and should be routinely used
Twins delivery…cesarean or vaginal
Vaginal delivery is recommended as long as first has a cephalic presentation and appropriately trained physicians and facilities.
Elective delivery of uncomplicated diamniotic/dichorionic twins
at 37 weeks
Epidural anesthesia is associated with
Longer first and second stages of labor
Increased incidence of:
- Fetal malposition
- Use of oxytocin
- Assisted vaginal deliveries
Difference in outcomes for operative vaginal delivery using a vacuum device compared to forceps
Vacuum
- Less maternal trauma
- Increase risk of neonatal cephalohematoma and retinal hemorrhage
When delivering occiput posterior presentation, what should first be considered for assisted vaginal delivery
Attempt manual rotation or forceps rotation if there is an experienced clinician.
Operative vaginal delivery with sequential use of a vacuum device and forceps has been associated with
Worse neonatal outcomes than use of a single instrument
Morbidity increase with failed operative vaginal delivery followed by cesarean delivery in the setting of fetal distress
For suspected macrosomia, when is primary cesarean delivery in uncomplicated non-diabetic pregnancy a possible indications?
Estimated fetal weight is >5,000 grams
When is shoulder dystocia associated with instrumental vaginal delivery and vacuum extractor use
Use in excess of 10 minutes or more than five tractive efforts, and should be conducted with caution
Instrumental vaginal delivery and vacuum extractor use in excess of 10 minutes or more than five tractive efforts is a prominent risk factor for
Neonatal brachial plexus palsy
Mnemonic for approach to shoulder dystocia
HELPERR H = call for Help E = Evaluate for Episiotomy L = Legs - McRoberts Maneuver P = Suprpubic Pressure E = Enter - rotational maneuvers R = Remove the posterior arm R = Roll the patient to her hands and knees
First choice for prevention of post-partum hemorrhage
oxytocin
Advantages of misoprostol in prevention of postpartum hemorrhage compared to oxytocin
Also effective
Inexpensive
Heat stable
Simple to administer
Why is oxytocin used instead of misoprostol for postpartum hemorrhage
Oxytocin is more effective and has less side effects
Medication for more than average bleeding during and after a delivery (postpartum hemorrhage)
Methylergonovine
gravid uterus
pregnant uterus that is entrapped in the pelvis between the sacral promontory and pubic symphysis
What should occur in pregnant women who suffer significant blunt uterine trauma beyond 11 weeks’ gestation
Screening for fetomaternal transfusion (e.g., Kleihauer Betke - test for both maternal and fetal blood)
Timing of emergency hysterotomy for maternal cardiac arrest to improve maternal and neonatal outcomes
4 minutes
In early postpartum hemorrhage, what threshold volume of blood loss requires immediate maternal resuscitation measure using an interdisciplinary team approach
1500 mL
What are the stages of labor
First stage: The time of the onset of true labor until the cervix is completely dilated to 10 cm.
Second stage: The period after the cervix is dilated to 10 cm until the baby is delivered.
Third stage: Delivery of the placenta
The first stage of labor is the longest and involves three phases:
Early Labor Phase –The time of the onset of labor until the cervix is dilated to 3 cm.
Active Labor Phase – Continues from 3 cm. until the cervix is dilated to 7 cm.
Transition Phase – Continues from 7 cm. until the cervix is fully dilated to 10 cm.
TDAP during pregnancy recommendation
Between 27-36 weeks
