Labor and Delivery: First Half

cervical, irregular, bloody, contractions

Labor: Definitions

-Labor → regular uterine contractions with _______ changes

-Prodromal or “false” labor → ________ contractions and no cervical change

-Other potential signs of labor → maternal discomfort, ______ show, nausea/vomiting, and palpable ____________

childbirth, labor, baby, placenta, recovery

Phases of Parturition

-Parturition → __________, broken up into 3 phases 

-Phase 0 → prelude to parturition, aka pregnancy 

-Phase 1 → preparation for _____, aka late pregnancy 

-Phase 2 → process of labor, broken into 3 stages  

• Stage 1 → labor, broken down into early/latent and active labor 

• Stage 2 → delivery of ____

• Stage 3 → delivery of _________

-Phase 3 → parturition ________, aka postpartum

inactivity, conception, relaxes, progesterone

Phase 0: Prelude to Parturition

-Uterine quiescence → ________

-From ___________ to initiation of parturition

-Uterine smooth muscle ________, unresponsive to stimuli

-Myometrial contractility is suspended

-Mediators → __________, prostacycline, relaxin

preparation, ripening, softening, oxytocin, stretch, estrogen

Phase 1: Preparation for Labor

-Activation, from initiation of parturition to onset of labor

-Uterine __________ for labor

-Cervical ___________ → changes in extracellular matrix/cervical collagen leads to ___________

-Mediators → prostaglandin synthesis, _________ receptor expression, gap junction receptors in myometrium, uterine _______, and _________/progesterone

delivery, contractions, expulsion, labor, placenta, oxytocin

Phase 2: Process of Labor

-Stimulation, from onset of labor to _________

-Uterine ____________, cervical dilation, fetal and placental ___________

-Stages of labor → _____, delivery of baby, delivery of ________

-Mediators → fetal cortisol, DHEAS, placental estriol, _________, prostaglandins

shrinkage, fertility, breastfeeding, contractions

Phase 3: Parturient Recovery

-Uterine involution → _________ of the uterus to normal pre-pregnancy size 

-From delivery to restoration of ______

-Return to pre-pregnancy physiology and anatomy 

-Involution, cervical repair, ____________

-Mediators → oxytocin, which stimulates smooth muscle uterine ____________

opening, internal, shortening, ischial spine, posterior

Cervical Exam

-Dilation → _______ of cervix, specifically ________ os (0-10 cm)

-Effacement → __________/thinning of cervix (0-100%)

-Station → location of presenting part in relation to _______ _______ (-5 to 5+)

-Consistency → firm, medium, soft

-Position → ________, mid, anterior

favorable, higher, successful, effacement, predictive, 6, induction, ultrasound

Bishop Score

-Indicates how ________ the cervix is

-Higher the number, _________ the chance of a ___________ vaginal delivery

-Used to take dilation, effacement, station, consistency, and position into account. Now often just use dilation, _____________, and station only

• These are the most _________ factors

-<5 points = cervix unfavorable → use ripening agents

- >6 points = cervix favorable → proceed with _____________

-Cervical length by ____________ can also supplement or replace effacement in some practices

regular, 6, slow, induced, 10, intense, rapid, oxytocin

Stage 1: Labor

-Phase 1 → Early/latent labor 

• _________ contractions until _ cm cervical dilation

• ____ cervical dilation / longest stage

• Longer in _________ labors compared to spontaneous; longer in obese patients 

-Phase 2 → Active labor 

• 6 cm to __ cm dilation (complete) 

• More frequent/________ contractions and rapid cervical dilation 

• Primipara = 1.2 cm/hr and multipara 1.5 cm/hr 

• Similar between induced and spontaneous labor 

-May consider augmentation with __________ or membrane rupture 

pushing, pushing, delivery, anesthesia

Stage 2: Pushing and Delivery

-Fully dilated and ________, completed with delivery of baby

-2 phases

• Passive → complete dilation until patient begins ________

• Active → beginning of maternal pushing to ________

-Length affected by parity and regional ____________

after, placenta, 30, oxytocin, fundal, lengthening, blood, rebound

Stage 3: Delivery of Placenta

-Begins ______ delivery of baby, and completed with delivery of _________

-Usually 5-10 minutes, up to __ minutes is normal

• Try manual extraction after 30 minutes

-________ infusion to help uterus contract

-______ massage

-Signs of placental separation → cord ________, gush of ______, and uterine fundal _________

involution, vitals, hemorrhage

Initial Hours Postpartum

-First 1-2 hours after delivery 

-Uterine _________ begins

-Monitor maternal _______ signs 

-Monitor for postpartum ____________

pelvis, engaged

Cardinal Movements of Fetus: Engagement (1)

-Fetal presenting part enters the ______ and becomes __________

-”Lightening” or “dropping”

descent, head, pelvis, contraction

Cardinal Movements: Descent (2)

-________ of the vertex will occur as fetal _____ passes down into the ______

-Influenced by shape of maternal pelvis and uterine ____________ strength

flexion, smallest

Cardinal Movements: Flexion (3)

-Head undergoes _______ which allows ____________ diameter to present into the pelvis

internal, sagittal, anteroposterior, pelvis

Cardinal Movements: Internal Rotation

-Upon descent into the midpelvis, the fetal vertex undergoes ________ rotation from a transverse position so that the ________ suture is parallel to the ______________ diameter of the pelvis (OA or OP)

beneath, pubic, deliver

Cardinal Movements: Extension

-As the vertex passes _________ and beyond the _____ symphysis, it will extend to _______

head, external, shoulders, body

Cardinal Movements: External Rotation

-Once the ____ delivers, _________ rotation by which the head turns back to prior transverse position occurs and the __________ may be delivered followed by fetal ____

perineum, flex, anterior, body

Normal Spontaneous Vaginal Delivery

-As fetal head is crowning, place one hand on the __________ to protect it

-Other hand is used to ____ head and keep it from extending too far

-Followed by delivery of ________ shoulder, posterior shoulder, and fetal ____

non-laboring, membrane, ripening, mechanical, oxytocin

Induction of Labor: Background

-Attempt to commence labor in a ___-_________ patient

-Methods

• __________ stripping/sweep

• Prostaglandins → misoprostol and cervidil, which are cervical ________ agents that reduce overall length of induction

• Foley balloon for __________ dilation

• Laminaria

• ___________

• Artificial rupture of membranes

diabetes, hypertension, age, demise, PROM

Indications for Induction of Labor

-Elective/Term → 39 to 39+6 weeks preferred time frame 

-Post-term pregnancy

-Pre-gestational/gestational _________

-Chronic ____________ or pregnancy-induced hypertension

-Advanced maternal ___

-Poor fetal tracing

-Intrauterine fetal ________

-Intrauterine growth restriction/placental insufficiency 

-Prelabor rupture of membranes (____)

-Oligohydramnios or polyhydramnios 

-Cholestasis 

-Chorioamniotis 

malpresentation, breech, herpes, cesarean, myomectomy

Contraindications for Induction of Labor

-Fetal ______________ or cephalic disproportion → _____, transverse, funic

-Placenta previa/vasa previa

-Active genital _______ outbreak

-History of uterine scar

• 2 or more prior low transverse __________ deliveries

• Prior classic cesarean delivery

• Prior ___________ for removal of uterine fibroid

advance, strength, oxytocin, slower, cessation, coupled

Labor Augmentation

-Help labor ________ and move along

-Increase contraction frequency/________

-Methods

• Ambulation

• ________ → considered as a treatment for protraction disorders, which is when labor progresses _______ than normal. Arrest disorders are a complete ___________ of progress

-Amniotomy/artificial rupture of membranes → more beneficial when _______ with oxytocin

fluid, pooling, infection, pH, basic, acidic, ferning

Rupture of Membranes: Diagnosis

-History and Physical Exam

• History of gush or persistent ____ leaking

• Sterile speculum exam → may see pooling 

• Digital cervical exam → limit frequency to reduce _________

• __ test of vaginal fluid → amniotic fluid is _____, while vaginal fluid is ______

• ________ test → look at fluid under microscope, let dry, see “ferning” 

• Ultrasound for AFI

• Tampon test

prelabor, preterm, age, infection, induce

Prelabor Rupture of Membranes: PROM

-_______ Rupture of Membranes

• PROM → at term

• PPROM → _______ (<37 weeks)

• Periviable PROM → < 24 weeks

-Management influenced by gestational ___ and presence of complicating factors (________, placental abruption, labor, abnormal FHR)

• PROM → if no spontaneous labor, then ______

• PPROM → give birth within 1 week

age, strep, infection, abnormal, bleeding, induction, observation

Management of PROM

-Consider gestational ___, fetal presentation, fetal well being, infection

-Collect group beta _____ screen

-Indications for delivery → intra-amniotic _______, ________ fetal testing, vaginal _________

-Most often proceed with _________ of labor

-May consider __________ for 12-24 hours to await spontaneous labor onset

20, 37, late, 33, 32, 28, higher

Preterm Birth

-Delivery occurring at or after __ weeks and before __ weeks 

• ____ preterm infants → between 34 weeks and 36 weeks and 6 days 

• Moderate preterm infants → between 32 weeks and __ weeks and 6 days 

• Very preterm infants → <__ weeks 

• Extremely preterm infants → <__ weeks 

-Non-Hispanic Black and Indigenous women have much ______ rates than white/Asian/Hispanic populations 

preterm, short, low, multiple, UTI

Preterm Birth Risk Factors

-History of _______ birth/PPROM

-_____ cervix

-____ maternal pre-pregnancy weight

• BMI < 18.5

-Tobacco use

-Substance use

-Short inter-pregnancy interval

-________ gestation

-Vaginal bleeding

-___/genital tract infections

age, abnormal, antibiotics, steroids, magnesium sulfate, steroids

Management of PPROM

-Plan is very dependent on gestational ___

-Deliver if _______ fetal testing, infection, or placental abruption

-Try to manage expectantly if before 34 weeks

• Latency _______

• _______ for fetal lung maturity

• Collect GBS

• Treat intra-amniotic infection is present

• __________ _______ for neuroprotection if < 32 weeks

• Periodic non stress tests and growth ultrasounds

-If 34-36 weeks, expectant management vs delivery

• ______ for fetal lung maturity/decrease respiratory morbidity

prolongs, infections, ampicillin, amoxicillin

Latency Antibiotics for PPROM

-_______ pregnancy

-Reduces maternal/neonatal __________

-Reduces gestational age dependent morbidity 

-If less than 34 weeks → 7 day course of IV _______ + erythromycin x 48 hours followed by PO ________ and erythromycin or azithromycin

length, 2, progesterone, shortening, cerclage

Managing Patient with a History of Preterm Birth

-Serial cervical _______ screening every _ weeks from 16-24 weeks

-Offer ___________ supplementation if cervical __________ noted

• Endometrin → vaginal progesterone

-Consider cervical ________

fibronectin, endometrium, increased, TVUS, hydration, nifedipine, steroids, admit

Concern for Patient with Threatened Preterm Labor

-History and physical

-Speculum and pelvic exam

• Fetal _________ sampling → fetal fibronectin is a protein made during pregnancy that is found between the ________ and amniotic sac. Positive testing indicates an _________ risk of premature labor

-____ for cervix length

-Continuous electronic fetal monitoring

-Ensure adequate ___________

-Consider tocolytics such as _______ or terbutaline

-Consider _______ for fetal lung maturity

-Observe or _____ if persistent UCs or cervical change

-Inform NICU

death, breathing, sepsis, jaundice, increased

Complications for Preterm Baby

-Increased risk of morbidity and _____ throughout childhood, especially during 1st year of life 

-Anemia

-_________ problems → apnea of prematurity, bronchopulmonary dysplasia, respiratory distress syndrome 

-Infections or neonatal _____

-Newborn ________

-Intraventricular hemorrhage 

-PDA

-Necrotizing enterocolitis 

-Retinopathy of prematurity

-___________ risk developmental challenges

nulliparous, cesarean, slower, active, cessation, 6, contractions

Abnormal Labor Patterns

-Affects ~20% of all labors ending in live birth

-Highest risk in term _____________ patient

-Most common reason for primary intrapartum _________ delivery

-Protraction disorders → ______ than normal progress or abnormally long ______ phase

-Arrest disorders → complete ________ of progress or descent

• Cervix > _ and ruptured membranes

• No change > 4 hours with adequate ____________

• No change > 6 hours with inadequate contractions

pelvic, fetal, malposition, uterine, strong, effort, anesthesia

Abnormal Labor Pattern Risk Factors

-Also called “labor dystocia”

-Passage → _____ dystocia

• Abnormally shaped pelvis

• Cephalopelvic disproportion

• Inadequate pelvis

-Passenger → _____ dystocia

• Macrosomia

• Fetal malformation or ___________

-Power → _____ dystocia

• Contractions are not adequate/______ enough

• Poor maternal ______

• Neuraxial __________

older, obesity, short, macrosomia

Factors Associated with Protracted Labor

-Uterine Factors (Hypocontractile Uterine Activity)

• _____ maternal age, uterine abnormality, maternal ________, neuraxial anesthesia, nulliparity, tocolytics, uterine relaxants, infection

-Pelvic Factors

• Contracted pelvis/prominent sacrum, _____ stature, high station at full dilation

-Fetal Factors

• Fetal anomaly resulting in CPD, non occiput anterior, LGA/__________

first, strong, coordinated, fetus

Hypocontractile Uterine Activity

-Most common risk factor for protraction/arrest disorder in _____ stage of labor

-Uterine activity not sufficiently _____ or not appropriately ___________ to dilate cervix or expel _____

frequent, ret, recover, pitocin, nifedipine

Hypercontractile Uterine Activity 

-Tachysystole/Uterine hyperstimulation

-Contractions too _______,  > 5/10 minute

-Uterus cannot ____

-Fetus may not have time to ________ between contractions 

-Consider decreasing/turning off ______ or give tocolytics such as terbutaline or _______

palpation, pressure, 200

Monitoring Uterine Activity

-Qualitative → _______, external tocodynamometry

-Quantitative → intrauterine _______ catheter (IUPC) to monitor montevideo units

• MVUS < ___, not adequate

endometritis, hemorrhage, operative, urinary

Maternal Complications of Abnormal Labor

-Infection → chorioamnionitis or __________

-Exhaustion

-Postpartum ___________

-Trauma

• Increased risk ________ delivery (vacuum or forceps vs cesarean)

• Increased risk of episiotomy

• Increased risk of perineal lacerations

-_______ retention

decelerations, variability, NICU, sepsis

Fetal Complications of Abnormal Labor

-Fetal distress

• Repetitive late _____________

• Bradycardia

• Tachycardia

• Loss of _________

-Meconium

-Increased risk of admission to _____

-Respiratory distress syndrome

-Neonatal ______