OB

NORMAL LABOR

Refers to the presence of regular uterine contractions that cause progressive dilatation and effacement of the cervix and fetal descent.

OBSTRUCTED LABOR

In spite of strong contractions, the fetus cannot descend through the pelvis because of the presence of an unsurmountable barrier preventing its descent.

OBSTRUCTED LABOR

Can occur anywhere in the pelvis but usually occurs at the pelvic brim.

OBSTRUCTED LABOR

Can result in prolonged latent, active or expulsive phase depending on which area of the birth canal

the obstruction is present.

inlet

1st stage is prolonged if obstruction is at the

outlet

2nd stage is prolonged if obstruction is at the

Bandl’s ring

a late sign of obstructed labor

OBSTRUCTED LABOR: Deliver fetus-dead

CS or craniotomy

OBSTRUCTED LABOR: Deliver fetus-CPD

CS

OBSTRUCTED LABOR: Deliver fetus-fully dilated

Forceps

PROLONGED LATENT PHASE

• starts from onset of regular uterine contractions to onset of active phase (0-3 cm)

− prolonged if exceeds more than 8 hours

PROLONGED ACTIVE PHASE

prolonged if more than 12 hours

PROTRACTION DISORDER

• slower than normal labor progress

− most common abnormality of labor

PROLONGED SECOND STAGE: NULLIPARA

2 hours without analgesia conduction, 3 hours with conduction

PROLONGED SECOND STAGE: MULTIPARA

1 hour without analgesia conduction, 2 hours with conduction

PROLONGED SECOND STAGE

Management

a. Delivery can be achieved via Forceps or vacuum extraction

b. If above measures fails or fetal distress occurs, CS

fetal anoxia and death

Excessive pushing and prolonged holding of breath should be discouraged because maternal expulsive efforts exert pressure in the uterus which reduces the delivery of O2 to the placenta, and consequently decreases O2 supply to the fetus , which can lead to

ARREST DISORDERS

• Complete cessation of progress

− Active phase disorders characterized by lack of fetal descent and dilatation

− Uterine contractions with normal frequency and intensity but cervix does not dilate and fetus does not descend. →same cause and management as protraction disorders.

Arrest of Dilatation

absence of progress in cervical dilatation for more than 2 hours in nullipara and 1 hour in multipara.

Arrest of Descent

Absence of progress of fetal descent for more than 2 hours in nullipara and 1 hour in multipara. Most common cause is CPD.

Failure of Descent

Absence of fetal descent in the 2nd stage of labor.

DYSTOCIA

A broad term referring to prolonged labor (any labor that lasts more than 24 hours) caused by an abnormality or a combination of abnormalities in the essential factors of labor.

Uterine Dysfunction

Abnormalities of Passageway

Fetal Dystocia

TYPES OF DYSTOCIA

PELVIC DYSTOCIA

Occurs when there is narrowing in one or more important diameters of the pelvis: inlet, mid pelvis, outlet.

Gynecoid and Anthropoid

– good prognosis for vaginal delivery

Android and Platypeloid

poor prognosis for vaginal delivery.

Inlet Dystocia

is defined as anteroposterior diameter >10 cm, greatest transverse diameter that is > 12 cm, or diagonal conjugate >11.5 cm.

INLET CONTRACTURE

Can be due to several conditions including flat pelvis.

Lack of engagement between 36th and 38th week of pregnancy in primiparas is an important sign of pelvic contraction.

MIDPELVIS CONTRACTURE

Most common pelvic dystocia. Occurs when the sum of the interspinous and posterior sagittal diameters of the mid pelvis is <13.5 cm.

MIDPELVIS CONTRACTURE

Fetus is able to engage, but due to the narrowed diameter of the mid pelvis, the fetal head is prevented from rotating internally from transverse to AP diameter.

Outlet Dystocia

occurs when the bi-ischial diameter (distance between ischial tuberosities) is < 11 cm

SHOULDER DYSTOCIA

After delivery of head, the anterior shoulder is trapped and arrested behind the symphysis pubis.

LEGS (Mc Roberts maneuver)

– done by flexing the legs of the parturient sharply over the abdomen.

Gaskin maneuver

roll patient onto her hand and knees or the “ALL FOURS” position to increase pelvic diameter (via X ray)

Zavanelli maneuver

– cephalic replacement followed by CS

UTERINE DYSFUNCTION

May be caused by any or a combination of the following conditions:

• Pelvic contraction

• Fetal malposition

• Over distention

• Excessive rigidity of the cervix

Hypotonic Uterine Contraction

Occurs during active phase

− Characterized by:

• weak and infrequent contractions which are insufficient to dilate the cervix

• uterus is easily indented at the peak of contraction because the strength does not rise beyond 25 mm Hg

• contractions are not painful because of their poor intensity

Hypertonic Uterine Contraction

Encountered in the latent phase of labor.

− Characterized by uncoordinated, too frequent contractions that tend to be more painful. The uterus does not relax completely between contractions.

− Excessive pain is caused by hypoxia of the uterine tissue from inadequate relaxation in between contractions.

PRECIPITATE LABOR AND DELIVERY

− Occurs within 3 hours from onset of contraction to delivery of baby.

− Occurs without warning.

Precipitate Dilatation

– cervical dilatation is progressing at 5 cm or more per hour in nulliparas, 10 cm or more per hour in multiparas.

Precipitate Descent

fetal descent is progressing at 5 cm or more per hour in nulliparas, 10 cm or more per hour in multiparas.

UTERINE RUPTURE

Tearing of uterine muscles occurs when the uterus can no longer withstand the strain.

− Rare but often a fatal complication of labor.

Complete Rupture

Woman experiences a sudden excruciating pain at the peak of a contraction, and then contractions stop altogether.

Incomplete Rupture

Localized tenderness and persistent pain over the abdomen.

- Contractions may still continue or stop but no progress in cervical dilatation will be observed.

- Vaginal bleeding may or may not occur because blood pools in the peritoneal cavity.

PHYSIOLOGIC RETRACTION RING

• Upper contracting portion that becomes thicker and shorter as labor progresses.

• Lower passive portion that distends gradually to accommodate the descending fetus.

PATHOLOGIC RETRACTION RING

Uterine contractions become stronger and more

frequent in an effort to overcome the obstruction

until it reaches a state of tonic contraction when the

uterus no longer relaxes.

BANDL’S (PATHOLOGIC RETRACTION) RING

A horizontal indention running across the abdomen or division of the two uterine segments that become very prominent which was caused by the continuous retraction of the upper segment and the over distention of the lower uterine segment.

pathologic retraction ring

Administration of IV Morphine Sulfate or inhalation of Amyl Nitrate may be given to relax the uterus and relieve __________

INADEQUATE VOLUNTARY EXPULSIVE FORCES

Bearing down efforts of the mother is not adequate to generate sufficient intra-abdominal pressure to propel the fetus.

UTERINE INVERSION

Uterus is partly or completely turned inside out.

− Serious complication of 3rd or 4th stage of labor.

Turtle Sign

: shoulder dystocia becomes obvious when the fetal head emerges and then retracts

against the perineum.

ABNORMAL LIE

Where the long axis of the fetus is not lying along the long axis of the mother’s uterus.

• Transverse

• Oblique

• Unstable

MALPOSITION

Where the fetus is lying longitudinally and the vertex is presenting, but not in Occiput Anterior (OA) position.

Occiput Posterior (OP)

– A malposition of vertex presentation

– Arrested labor may occur when head does not rotate and/or descend.

– Delivery maybe complicated by perineal tears or extension of an episiotomy.

Occiput Transverse (OT)

Is the incomplete rotation of Occiput Posterior to Occiput Anterior, which results in a horizontal or transverse position of the fetal head.

MALPRESENTATION

Where the fetus is lying longitudinally, but presents in any manner other than vertex.

• Breech

• Brow

• Face

• Shoulder

• Compound

Brow Presentation

− most uncommon of all presentation

− babies born vaginally experience extreme facial edema

Face Presentation

Occurs when head is hyper-extended, the face is the presenting part, the chin (mentum) is the denominator

chin is in anterior position

uterine contractions are strong, head is small, shoulders have already entered the pelvis and there is no pelvic contraction, vaginal delivery is possible but longer than usual. Forceps may be used to hasten 2nd stage

chin is in posterior position (RMP, LMP)

vaginal delivery may be impossible and dangerous if attempted because it can lead to transverse arrest. CS

Sincipal Presentation

Occurs when the larger diameter of the fetal head is presented.

− Labor progress is slowed with slower descent of the fetal head.

Breech Presentation

– Most common cause of fetal malpresentation.

Frank Breech

Buttocks comes first

– Hips are flexed, knees are extended

Complete Breech

Buttocks comes first

– Hips and knees are flexed

Footling (Double or Single)

– 1 or both feet come first

– Rare in term, common in premature

Kneeling Breech

– 1 or both legs extended at the hips & flexed at the knees

– Extremely rare

External Cephalic Version (ECV)

breech presentation is present at or after 37 weeks

• vaginal delivery is possible

there are no contraindications (fetal abnormality, placenta previa, uterine bleeding, previous uterine surgery, hypertension, multiple gestation, Oli or Polyhydramnios)

Risk of ECV

Placental abruption

- PROM

- Cord accident

- Transplacental Hemorrhage

- Fetal bradycardia

Vaginal Breech Delivery

may be attempted if:

• there is no pelvic contraction

• fetal weight is not more than 3,500 grams

• there is experienced/skilled personnel in breech delivery

• spontaneous labor occurs with progressive cervical dilatation

• no evidence of feto-pelvic disproportion

Spontaneous Breech Delivery

born without traction or manipulation from OB

Partial Breech Extraction

born up to the umbilicus; rest of the body is extracted

Total Breech Extraction

entire body is extracted by OB

Pinard’s

– done in breech with extended leg

once the groin is visible, gentle pressure can be applied to abduct the thigh and reach the knee

The knee can be flexed with pressure in the popliteal fossa & the leg delivered.

– anterior leg is always delivered first

Loveset Maneuver

automatically corrects any upward displacement of arms

− Baby’s trunk is rotated with downward traction, holding at the iliac crest so that posterior shoulder comes below the symphysis pubis, arm is delivered by flexing the shoulder followed by hooking at the elbow and flexing it, followed by bringing down the forearm like a “hand shake”.

Same procedure is repeated by reverse rotation of 180° so that anterior shoulder comes below the symphysis pubis.

Mauriceau-Smellie-Veit Maneuver

used to extract the head after delivery of infant’s body

− Baby is rested on obstetrician’s supinated non-dominant hand, with limbs hanging on either side.

− Non-dominant Index & middle fingers are placed on malar bones, dominant index & ring fingers are placed on shoulders with middle finger on sub-occipital region.

Prague Maneuver

used when the back of the fetus fails to rotate to the anterior.

− The operator delivers the shoulders with one hand, while making pressure above the symphysis pubis with the other hand.

Bracht Maneuver

– Delivery by extension of the legs and trunk of the fetus over the symphysis pubis and abdomen of the mother

The fetal head is born spontaneously as the legs and trunk are lifted above the maternal pelvis, and as the body of the infant is extended by the operator.

Abdominal Rescue

– fetus is replaced when fully deflexed head is entrapped and cannot be delivered vaginally. CS follows

Cleidotomy

– involves cutting of shoulder to facilitate delivery. Also used in shoulder dystocia

Shoulder Presentation

Occurs when fetus assumes a transverse or oblique lie

− The fetus does not engage in this presentation so there is a great danger of cord prolapsed after membranes have ruptured

Compound Presentation

A fetal presentation in which an extremity presents alongside the part of the fetus closest to the birth canal. The majority of compound presentations consist of a fetal hand or arm presenting with the vertex.

Breech

Vaginal delivery +- ECV / CS

Face

Vaginal delivery (chin anterior), CS (chin posterior)

Brow

Cesarean Section (CS)

Shoulder

Cesarean Section (CS)

Compound

Replacement of prolapsed arm →vaginal delivery / Cesarean Section

FETAL DISTRESS

Refers to the presence of signs in a pregnant woman before or during childbirth that suggest that the fetus may not be well.

PROLAPSE UMBILICAL CORD

Occurs when the cord passes out the uterus ahead of the presenting part.

− Occurs after membranes have ruptured when the fetus is not yet engaged or does not completely cover the pelvic inlet.

PROLAPSE UMBILICAL CORD

ALWAYS lead to cord compression as the presenting part descends in the birth canal.

Polyhydramnios

An abnormally high amount of amniotic fluid

Overt Umbilical Cord Prolapse

Descent of the umbilical cord past the presenting fetal part.

- Cord is through the cervix and into or beyond the vagina.

- Requires rupture of membranes.

- This is the most common type of cord prolapse.

Occult Umbilical Prolapse

Descent of the umbilical cord alongside the presenting fetal part, but has not advanced past the presenting fetal part.

- Can occur in intact or ruptured membranes.

Funic (Cord) Presentation

Presence of the umbilical cord between the presenting fetal part and fetal membranes.

- The cord has not passed the opening of the cervix.

- The membranes are not yet ruptured.