Stages of labor

STAGES OF LABOR

FIRST STAGE

Latent phase – Cervical effacement and early dilatation
Active phase – Rapid cervical dilatation Protraction disorder of the active phase (dilatation)
SECOND STAGE (pushing)
Primip – 30min – 3 hr, multip – 5 –30 min
Mechanisms of Labor

Descent – uterine contractions, maternal pushing, gravity Internal Rotation – Fetal head from transverse/oblique to occiput anterior Extension – Vaginal outlet is upward and forward Crowning – largest diameter of fetal head encircled by vulvar ring External Rotation – delivered head returns to original position to align with back and shoulders Expulsion – anterior shoulder delivers under symphysis
THIRD STAGE

Delivery of the placenta – avg 2 –10min Signs of placental seperation 1) Fresh show of blood 2) Umbilical cord lengthens 3) Fundus of uterus rises up 4) Uterus becomes firm and globular First degree –vaginal epithelium or perineal skin Second degree – extends into subepithelial tissues or perineum with or without involvement of muscles of the perineal body Third degree – involvement of the anal sphincter Fourth degree – involvement of the rectal mucosa FOURTH STAGE

Follow vitals and any signs of postpartum hemorrhage
INDUCTION OF LABOR – labor initiated by artificial means
AUGMENTATION OF LABOR – stimulation of labor after it has begun spontaneously
Indications – Maternal or Fetoplacental

Bishop Score–
Cervix
High score 9-13 High likelihood of vaginal delivery Low score <5 decreased likelihood of success (65-80%) Cervical Ripening – mechanical +/- pharmacological Intracervical dilators – Foley catheter, Laminaria Prostaglandin E gel or vaginal insert, new – misoprostol (Cytotec)
Oxytocin – Identical to natural pituitary peptide
Amniotomy
ACTIVE MANAGEMENT OF LABOR
1) Nulliparous – spontaneous labor, singleton pregnancy, cephalic 2) Prenatal education classes 3) Constant attendance in labor with labor nurse specialist/midwife 4) Peer review of all c-sections 5) Not admitted without clear diagnosis of labor Regular/painful contractions with one of the following: complete cervical effacement, rupture of membranes, bloody show 6) Amniotomy upon admission 7) Regular exams for progress 8) Oxytocin if <1cm/hr or no descent for an hour
DELIVERY

Position, prep and drape
Crowning – decide if needs episiotomy
SUPPORT THE PERINEUM!
Ritgen maneuver- increases extension of head Understand the force / counterforce – you apply counterforce to control the delivery
Head delivered – check for cord
Suction airway
Deliver anterior shoulder – downward traction
Deliver posterior shoulder –upward
Deliver body
Clamp cord/suction airway – hand off baby
Check vagina/perineum
Prepare to delivery placenta – mild traction on cord with counterforce on uterus
SHOULDER DYSTOCIA “the scariest event in obstetrics”
Anterior Shoulder is impacted behind symphysis pubis DON’T APPLY MORE TRACTION – need to disengage anterior shoulder! McRoberts maneuver – Flex maternal thighs Wood’s screw – try to rotate posterior shoulder upward Zavanelli maneuver – manually push head into vagina/uterus followed by stat c/section
Complication – fractures of humerus, clavicle, Erb’s palsy – brachial plexus injury

RETAINED PLACENTA

Source: http://uicchicago.sharpschool.com/UserFiles/Servers/Server_442934/File/OBGYN%20Med%20Ed/STUDENTS/Lectures/STAGES%20OF%20LABOR-App.pdf