3- Normal Labor, Delivery & Puerperium Flashcards
Labor is defined as uterine activity that results in what?
Progressive dilation and effacement of the cervix
What is defined as thinning of the cervix described as a % of a normal 4-5cm long cervix?
Effacement
What is defined as placement/ degree of descent of the presenting part of the fetus in the maternal pelvis in relation to the ischial spines?
Station, scale of -3 to +3
What is important when evaluating for rupture of membranes?
Sterile speculum exam
What test yields high false positives due to urine, blood, semem, BV, or trichomoniasis, and what is the expected result if ruptured membranes?
Nitrazine paper testing
Turns blue in presence of alkaline amniotic fluid
What test involves visualization of an air dried sample of amniotic fluid, and what is the expected result if ruptured membranes?
“Fern test”
Fern pattern → admitted to hospital
What test for ruptured membranes only requires a small sample, is very specific and includes a vaginal swab with (-) or (+) dipstick results?
Amniosure
How is the “lie” (transverse) described with respect to fetal position?
Long axis of fetus vs long axis of mother’s body
What stage of labor is defined as onset of regular uterine contractions through full cervical dilation?
1st, latent and active phases
What stage of labor is defined as complete cervical dilation through delivery of infant and differs by race and parity?
2nd
What signs are a/w the 2nd stage of labor and aid in the descent/ expulsion of the fetus?
Uterine contractions and maternal expulsive efforts
What stage of labor is defined as the interval between delivery of the fetus and detachment/ expulsion of the placenta?
3rd, ~ 30 min
What are defined as changes in the position of the fetal head in relationship to the fetal body as it nagivates the maternal pelvis?
Cardinal movements of labor
(should be thought of as a continuous motion of connected movements)
What are the 6 cardinal movement of labor?
Engagement
Flexion
Descent
Internal rotation
Extension
External rotation
What complications are a/w the 3rd stage of labor?
Hemorrhage
Retention of placenta
Uterine inversion
What signs indicate separation of the placenta? (4)
Uterus rises in abdomen
Globular configuration
Gush of blood
Lengthening of umbilical cord
What stage of labor is defined as the interval between delivery of the placenta and the subsequent 2 hours postpartum and what is it a/w?
4th
A/w major hemodynamic changes of maternal CV system
How is adequate labor defined?
3-5 contractions in 10 min averaged over 30 min
What factors affect maternal expulsive efforts?
Maternal strength
Consciousness/ sedation
Pain
Regional anesthesia
What does an external tocodynamometer measure with respect to uterine contractions?
Frequency and duration of contractions
NOT intensity
What does an internal tocodynamometer measure with respect to uterine contractions?
Frequency, duration, and intensity
(more precise)
What is considered a macrosomic infant?
> 4500 grams
How is the “passenger” position defined?
Relation of fetal presenting part to R or L side of maternal pelvis
What are the shapes of the posterior and anterior fontanel?
Posterior- triangle
Anterior- diamond
What is the most common presenting fetal position in labor?
Left occiput anterior (LOA)
What are the 4 basic female pelvic types?
Gynecoid, anthropoid, android, platypelloid
What female pelvic type is most common and best suited for childbirth?
Gynecoid
What female pelvic type is the most unfavorable for delivery?
Android
What female pelvic type is the least common?
Platypelloid
How is labor pattern affected by analgesia in true labor?
Not altered
What characteristics are concerning for false labor?
Contractions = irregular intervals/ duration (Braxton-Hicks)
Contraction intensity varies
Relief from sedation/ hydration
In addition to intermittent auscultation, what is used for fetal monitoring?
Continuous electronic fetal monitoring (CEFM)
- External- US
- Internal- ECG
What is considered normal variability for amplitude change of FHR?
(variability = beat to beat changes)
6-25 bpm
(<5 = conern for hypoxia)
How are periodic changes in FHR defined?
Longer than beat to beat changes - accelerations or decelerations
What type of periodic deceleration of FHR is physiologic, mirrors shape of contraction, and due to head compression?
Early
What type of periodic deceleration of FHR has variable timing, shape and severity with relation to the contraction, and is due to cord compression?
Variable (v-shape)
What type of periodic deceleration is caused by fetal hypoxia, is omnious, and can be the result of placental insufficiency, or maternal hypotension/ hypoxia?
Late
Basic antepartum testing is meant to eval a fetus who is at higher than normal risk for intrauterine fetal complications that can lead to what?
(fetal kick counts, non-stress testing, contraction stress testing, BPP)
Placental insufficiency and fetal acidosis
What is considered a normal result on a non-stress test?
2 accelerations w/i 30 min a/w movement
What 4 parameters are evaluated as part of the biophysical profile (BPP)?
Amniotic fluid assessment (deepest vertical pocket- 2cm)-
Gross fetal movement
Tone
Fetal “breathing” activity (30 sec)
How is the BPP scored?
Each parameter = +2 or 0 (no partial scores
W/ non-stress test, max score = 10
What contraction stress test result is defined as 3 contractions in 10 minutes with no late decelerations and is considered reassuring?
Negative
What contraction stress test result is defined as late decelerations or significant variable decelerations with > 50% of the contractions in a 10 min period and is considered non-reassuring?
Positive
What contraction stress test result is defined as late decelerations with < 50% of the contractions in 10 min?
Equivocal
What structures are affected in a 1st degree obstetric laceration?
Vaginal mucosa or perineal skin
Not underlying tissue
What structures are affected in a 2nd degree obstetric laceration?
Underlying subcutaneous tissue
NOT rectal sphincter/ mucosa
What structures are affected in a 3rd degree obstetric laceration?
Through rectal sphincter
NOT rectal mucosa
What structures are affected in a 4th degree obstetric laceration?
Into rectal mucosa
What are the most common episiotomy locatioins?
1, 4
What can be used for induction of labor?
Prostaglandin gel/ device
Misoprostol
Pitocin
“Stripping” membranes
Amniotomy (artificial rupture of membranes)
What are the risks a/w induction of labor? (4)
Uterine tachysystole → decreased oxygen exchange/ risk of fetal hypoxia/ acidosis
Increased risk of C-section (esp if “unfavorable cervix”)
Umbilical cord prolapse (w/ amniotomy)
Intra-amniotic infection
What Bishop scores are considered high and low risk?
0-4 = high risk for failed vaginal delivery
8-13 = highest chance for successful vaginal delivery
What are the different types of OB anesthesia?
Psychoprophylaxis
IV
Epidural (most common)
Spinal (C-section)
Inhaled
General
How is puerperium defined?
Period following delivery of baby/ placenta to ~ 6 weeks postpartum
What anatomic changes are a/w puerperium?
Uterus involutes
Cervix loses vascularity/ shinks
Anovulation (6-12 weeks)
Vagina decreases in size/ is dry
How long is a patient typically hospitalized after vaginal birth vs C-section?
Vaginal- 1-2 days
C-section- 2-4 days
When is a postpartum exam performed?
4-6 weeks
When does lactation begin during puerperium?
Colostrum after 1st day, mature milk after 3rd-5th day
What type of twin gestation has no genetic predisposition and no increased risk with fertility rx?
Monozygotic (identical twins)
What type of twin gestation has a genetic predisposition increased risk with fertility rx?
Dizygotic (fraternal twins)
(2 eggs, 2 sperm)
What is the only possible type of gizygotic twin gestation?
Diamniotic/ dichorionic
What are the risks a/w dizygotic twins, although least high risk of twin gestation?
Preterm labor/ delivery
Intrauterine growth restriction
Increased risk of fetal anomalies
Increased risk of C-section
Monozygotic twin pregnancy is the most complication type of twin pregnany and is a/w what complications, in addition to those a/w dyzygotic twin pregnancy?
(dizygotic risks = preterm labor/ delivery, intrauterine growth restriction, increased risk of fetal anomalies, increased risk of C-section)
Twin-twin transfusion
Cord entanglements
Increased risk of growth restiction/ preterm birth
With what type of twin pregnancy can twin-to-twin transfusion syndrome occur?
Monochorionic/ diamniotic
What is the result of arteriovenous malformations in the placenta leading to twin-to-twin transfusion syndrome?
Unbalanced transfusion/ circulation → one becomes anemic/ low fluid and one becomes polycythemic/ fluid overloaded
At what point in pregnancy should twin-to-twin transfusion syndrome be considered?
2nd trimester
US eval q 2 weeks starting @ 16 weeks
