Labor Complications: Fetal Position

Problems with the Passenger

• Problems related to the fetus and its position during labor and delivery

Abnormal Lie

• Fetal long axis isn't aligned with the mother's uterus
• Includes transverse, oblique, and unstable positions
• Longitudinal position (cephalic or breech) is normal

Malposition

• Fetus lies longitudinally with vertex presenting but not in Occiput Anterior (OA) position

Occiput Posterior (OP)

• Vertex presentation malposition
• May cause arrested labor due to failure of head rotation or descent
• Can lead to perineal tears or episiotomy extensions during delivery

Occiput Transverse (OT)

• Incomplete rotation from Occiput Posterior to Occiput Anterior
• Results in fetal head being in horizontal or transverse position

Factors Favoring Malposition

• Pendulous abdomen in multiparous women
• Anthropoid or Android pelvic brim
• Flat sacrum
• Anterior placenta

Diagnosis

• Labor is normal except for prolonged second stage (over 2 hours)

Abdominal Examination

• Lower abdomen may be flattened
• Fetal back is hard to palpate
• Fetal parts felt anteriorly
• Heart sounds heard in the flanks

Vaginal Examination

• Posterior fontanel located towards the sacral-iliac joint
• Anterior fontanel easily felt if the head is deflexed
• Fetal head is molded, making station and position diagnosis difficult

Management

• Spontaneous rotation into the occiput anterior position occurs in 90% of cases, especially with good uterine contractions and average sized fetus
• In the second stage of labor, an emergency C-section is considered in the event of arrested labor

Malpresentation

• Fetus presents longitudinally but in a way other than vertex
• E.g., Breech

Vertex Malpresentation

Brow Presentation

• Uncommon
• Babies born vaginally experience extreme facial edema

Assessment

• Abdominal exam: more than half of fetal head above the symphysis pubis
• Vaginal exam: anterior fontanel and orbits felt

Management

• Usually requires Cesarean Section (CS)

Face Presentation

• Head is hyper-extended, face is presenting part, chin (mentum) is denominator
• The mechanism of labor: descent, internal rotation, flexion, extension, external rotation, & expulsion

Maternal Causes

• Lax uterus
• Contracted pelvis
• Placenta previa
• Multiple gestation
• Occiput posterior

Fetal Causes

• Large fetus
• Congenital malformation
• Multiple cord coil
• Musculoskeletal issues
• Tumors around neck

Diagnosis

• Absence of engagement
• Vaginal exam: mouth, nose, malar bones, orbital ridges felt
• UTZ confirms diagnosis

Management

• If chin is anterior (LMA or RMA), vaginal delivery is possible albeit longer, forceps may be used
• If chin is posterior (RMP, LMP), vaginal delivery can be dangerous

Sincipital Presentation

• Large diameter of fetal head presents
• Slowed labor progress due to slower descent

Presenting Part Diameter

• Suboccipitobregmatic (flexed vertex presentation) is 9.5cm
• Suboccipitofrontal (partially deflexed vertex) is 10.5cm
• Occipitofrontal (deflexed vertex) is 11.5cm
• Mentovertical (brow) is 13cm
• Submentobregmatic (face) is 9.5cm

Breech Presentation

• Common malpresentation

Types

• Frank: buttocks first, hips flexed, knees extended
• Complete: buttocks first, hips and knees flexed
• Footling: one or both feet first, more common in premature births
• Kneeling: one or both legs extended at hips and flexed at knees; extremely rare

Breech Assessment

• Leopold's Maneuver to feel the head on the fundus
• Ascultation for fetal heart sounds in the upper quadrant
• Vaginal examination to feel buttocks and/or feet and assess for thick, dark meconium

Breech Etiology

• Maternal factors: polyhydramnios, oligohydramnios, uterine abnormalities, pelvic tumor, uterine surgery, contracted pelvis, previous breech delivery
• Fetal factors: prematurity, multiple pregnancy, fetal anomalies
• Placental: placenta previa

Breech Complications

• Cord prolapse
• Birth trauma (fractures, hemorrhage, organ rupture)
• Dysfunctional labor
• Meconium aspiration
• Intrauterine anoxia
• Fetal death

Breech Management

• Confirmation via ultrasound at or after 36 weeks
• If breech presentation is present at/after 37 weeks, vaginal delivery is possible, and there are no contraindications, External Cephalic Version (ECV) should be attempted
• Risks of ECV: placental abruption, PROM, cord accident, transplacental hemorrhage, fetal bradycardia
• Vaginal breech delivery may be attempted if: No pelvic contraction, fetal weight no more than 3,500 grams, experienced personnel and labor is spontaneous

Important Points for Vaginal Breech Delivery

• Do not rush
• Let mother expel fetus
• Keep fetus with back anterior
• Have forceps ready
• Have anesthetist and pediatrician present

Breech Delivery Techniques

• Spontaneous breech delivery = born without OB traction
• Partial breech extraction = born up to the umbilicus; rest is extracted
• Total breech extraction = entire body extracted

Breech Maneuvers

• Pinard’s: groin visible, abduct thigh and reach knee
• Loveset Maneuver: corrects upward arm displacement
• Mauriceau-Smellie-Veit: extracts infant head

Other Maneuvers

• Prague: Operator delivers shoulders with one hand and applies pressure on the symphysis pubis with the other hand
• Bracht: Delivery occurs with the extension of legs and trunk of baby to pubic symphysis
• Abdominal Rescue: fetus is replaced when fully deflexed and entrapped, followed by CS
• Cleidotomy: cutting clavicle to facilitate delivery; used in shoulder dystocia

Breech Management

• Regular assessment of POL: Contractions, effacement, dilatation, station, presentation
• Determine fetal condition through ultrasound: to determine any anomalies like microcephaly
• Cesarean section

Shoulder Presentation

• Fetus assumes a transverse or oblique lie
• Cord prolapse risk after membranes rupture

Shoulder Presentation Causes

• Lax uterine and abdominal muscles
• Contracted pelvis
• Uterine abnormalities
• Preterm fetus
• Placenta previa
• Multiple pregnancy

Shoulder Presentation Signs

• Horizontal uterus shape
• Fetal head and buttocks occupy sides of uterus

Shoulder Presentation Management

• External version before labor
• Cesarean section if the version fails

Compound Presentation

• Extremity presents alongside presenting part (usually hand or arm with vertex)

Compound Presentation Management

• Closely observe to see if the arm retracts
• Push prolapsed arm upward and head downward with fundal pressure if the arm prevents descent

Presentation Management Chart

• Breech – Vaginal delivery or ECV/ CS
• Face – Vaginal delivery (chin anterior); CS (chin posterior)
• Brow – Cesarean Section (CS)
• Shoulder – Cesarean Section (CS)
• Compound – Replacement of prolapsed arm leading to vaginal delivery, or Cesarean Section

Fetal Distress

• Signs that suggest fetus isn't well during pregnancy/childbirth
• Characterized by a decrease in movement sensed by the mother and meconium-stained amniotic fluid
• Abnormal cardiotocography patterns: tachycardia, bradycardia, decreased variability, late decelerations

Fetal Distress Causes

• "Fetal distress" causes included breathing problems and abnormal presentation
• May also include: multiple births, umbilical cord prolapse, Nuchal cord & Placental abruption

Fetal Distress - Treatment

• Current recommendations focus on specific signs/symptoms, assess, and remedy with intrauterine resuscitation
• Traditionally, rapid delivery via instrumentation or C-section

Prolapsed Umbilical Cord

• Cord passes out of uterus before presenting part
• Occurs after rupture of membranes when fetus is not engaged and involves cord compression
• Causes: polyhydramnios, long cord, malposition, prematurity, placenta previa, premature rupture

Prolapsed Umbilical Cord - Risk Factors

• Fetal malpresentation, polyhydramnios and prematurity
• Also includes: low birth weight, multiple gestation and spontaneous rupture of membranes

Prolapsed Umbilical Cord - Signs & Symptoms

• Cord protrusion/palpable in vagina/cervix in IE
• Fetal distress (variable deceleration in FHT)

Types of Umbilical Cord Prolapse

• Overt: Descents through cervix and beyond the vagina, needs membrane rupture
• Occult: cord beside the presenting part but hasn't advanced past it, occurs in intact/ruptured membranes
• Funic: cord between presenting fetal part and membranes, membranes are unruptured

Prolapsed Umbilical Cord - Management

• Prevention: assess FHT and bed rest after rupture
• Knee-chest/Trendelenburg or elevate presenting part upward with sterile gloves
• Cover exposed cord with saline compress
• Administer O2
• Immediate vaginal delivery if cervix fully dilated and no fetal distress
• Immediate CS if cervix not fully dilated or there's fetal distress