Normal Labor and DeliveryErick Caesarrani A., dr., SpOG, MKes

Definitions• Labor – Uterine contractions that result in effacement and dilatation of

the cervix.

• Braxton-Hicks – Uterine contractions NOT associated with cervical change.– Shorter in duration– Less intense– Over lower abdomen and groin– Resolve with ambulation

• Lightening – Descent of the fetal head into the pelvis

Definitions• Preterm labor – Prior to 37 weeks• Term – 37 to 42 weeks• Post term – After 42 weeks• Post dates – After 40 weeks

Normal Labor and Delivery• In order to maximize the patient’s chance at a

vaginal delivery it is important to understand the basics of labor and delivery:– Stages of labor– Mechanics of labor– Cardinal movements of labor– Delivery

Stages of Labor• 1st Stage

– Interval between onset of labor and full cervical dilatation

– 2 phases:• Latent – period between onset of labor

and point at which a change in slope of rate of cervical dilatation is noted.

• Active – Greater rate of cervical dilatation and usually begins around 2-3cm

Stages of Labor• 2nd stage

– Interval between full cervical dilatation and delivery– Duration

• Nulliparous – 2 hours• Multiparous – 1 hours

• 3rd stage– Delivery of the placenta and membranes– Duration – maximum of 30 minutes

Normal Labor and Delivery• In order to maximize the patient’s chance at a

vaginal delivery it is important to understand the basics of labor and delivery:– Stages of labor– Mechanics of labor– Cardinal movements of labor– Delivery

Mechanics of Labor (3P)• The Powers– Forces generated by uterine musculature– Frequency, amplitude, and duration of ctx’s– Observation, manual palpation, tocodynamometry,

intrauterine pressure catheter (IUPC)– Measured in Montevideo units

• Average strength of ctx’s (mmHG) x no. of ctx’s in 10 minutes• Adequate 200-250 MVUs

Mechanics of Labor• Passenger

– Fetal size• Abdominal palpation or Ultrasound• Macrosomia (>4500g) associated w/

failure to progress– Lie

• Longitudinal axis of fetus relative to longitudinal axis of uterus

• Longitudinal*, transverse or oblique

Mechanics of Labor• Passenger (cont)

– Presentation• Fetal part that directly overlies pelvic

inlet• Cephalic, breech, or shoulder• Compound – presence of >1 fetal

part overlying the pelvic inlet• Funic – umbilical cord presenting at

pelvic inlet• Malpresentation – any presentation

that is not cephalic with occiput leading

Mechanics of Labor• Passenger (cont)– Attitude

• Position of head with regard to fetal spine (ie: degree of flexion or extension)

• Flexion allows smallest diameter of fetal head to present at pelvic inlet

– Position• Relationship of a nominated site of presenting part to

denominating location on internal pelvis– Example: cephalic presentation

Mechanics of Labor

Mechanics of Labor

• Passenger (cont.)– Station

• Measure of descent of presenting part of the fetus through the birth canal.

– Multifetal Pregnancy• Increase probability of abnormal

lie and malpresentation in labor

Mechanics of Labor• Passenger (cont.)

– Leopold’s maneuvers• #1 – Correct dextrorotation of the

uterus with the back of one hand and delineate the fundus with the other to determine gestational age and/or appropriate size.

• #2 – Run hands down maternal abdomen on either side of fetus to determine fetal lie, identifying small parts and fetal spine

Mechanics of Labor• Passenger (cont.)

– Leopold’s maneuvers• #3 – Firmly grasp upper and lower

poles of fetus by placing fingers at uterine fundus and above symphysis to determine presentation and fetal size.

• #4 – Move hands in bilaterally from anterior superior iliac crests to determine whether or not the presenting part of the fetus is engaged in maternal pelvis. – Head regarded as unengaged if

examiner’s hands are see to converge below fetal head.

Mechanics of Labor• Passage

– Bony pelvis + soft tissues– X-ray pelvimetry now rarely used, having been replaced by a trial of

labor– 4 types of the female bony pelvis

Mechanics of Labor• Passage

Normal Labor and Delivery• In order to maximize the patient’s chance at a

vaginal delivery it is important to understand the basics of labor and delivery:– Stages of labor– Mechanics of labor– Cardinal movements of labor– Delivery

Cardinal Movements of Labor

• Engagement– Passage of widest diameter of presenting part to level

below the plane of the pelvic inlet– 0 station– Occurs earlier in nulliparous women (36 wks)

• Descent– Downward passage of presenting part through the

pelvis.• Flexion

– Occurs passively as the head descends due to the shape of the bony pelvis and resistance of pelvic floor soft tissues

– Allows smallest diameter of fetal head to pass through the pelvis.

Cardinal Movements of Labor• Internal Rotation

– Rotation of presenting part from original position (transverse) to anteroposterior position

• Extension– Occurs once fetus has

descended to the level of the introitus

– Base of occiput in contact with inferior margin of symphysis pubis

Cardinal Movements of Labor• External Rotation

– Return of fetal head to correct anatomic position in relation to the fetal torso

• Expulsion– Delivery of rest of fetus– Anterior shoulder delivered

first with rotation under the symphysis pubis

Normal Labor and Delivery• In order to maximize the patient’s chance at a

vaginal delivery it is important to understand the basics of labor and delivery:– Stages of labor– Mechanics of labor– Cardinal movements of labor– Delivery

How to effectively deliver a baby• Prepare for the delivery taking into account parity, progression of labor, presentation of fetus,

complications of labor• When head crowns and delivery is eminent, protect the perineum + downward pressure to

keep head flexed– Ritgen’s maneuver my help if delay in delivery of the fetal head

• Sterile towel used to palpate fetal chin through the rectum to apply upward pressure to facilitate extension of fetal head

• After delivery of head– Allow for external rotation (restitution).– Reduce nuchal cord– Suction fetal mouth and nares

• After clearing fetal airway– Place a hand on each parietal eminence to apply downward traction to deliver anterior shoulder– Followed by upward traction to deliver posterior shoulder

How to effectively deliver a baby• After complete delivery of infant

– Cradle in a single arm below the perineum to allow maximal blood transfer to infant

• Delivery of the placenta– 3 classic signs of placental

separation:• Lengthening of the umbilical

cord• Gush of blood from vagina• Change in shape of the uterine

fundus to a more globular appearance

How to effectively deliver a baby• Delivery of the placenta

– Active management of 3rd stage has been shown to reduce total blood loss• Brandt-Andrews Maneuver:

abdominal hand secures the uterine fundus to prevent uterine inversion while the other hand exerts sustained downward traction on umbilical cord

• Crede maneuver – cord is fixed with lower hand while the uterine fundus is secured and sustained upward traction is applied using abdominal hand

How to effectively deliver a baby• Inspect the placenta

– Abnormalities of lobulation– Site of insertion of umbilical cord into

the placenta• Marginal insertion –inserts into edge

of placenta• Membranous insertion – vessels

course through the membranes prior to attaching to placental disk

– Length (50-60cm)– 2 arteries and 1 vein

• Single umbilical artery associated with 20% risk of other structural anomalies.

Episiotomy• Indications :

– Shoulder dystocia– Breech delivery– Forceps or Vacuum extractor

deliveries– Occiput Posterior Positions– Instances in which failure to

perform an episiotomy will result in perineal rupture.

Type of Episiotomy

Characteristic Midline Mediolateral

Surgical repair Easy More difficult

Faulty healing Rare More common

Postoperative pain Minimal Common

Anatomical results Excellent Occasionally faulty

Blood loss Less More

Dyspareunia Rare Occasional

Extensions Common Uncommon

Dystocia• Dystocia literally means difficult

labor, characterized by abnormally slow labor progress.

• Abnormalities of the expulsive forces– Active Phase Disorder– Second Stage Disorder– Chorioamnionitis– Ruptured Membrane w/o Labor– Precipitous Labor

• Abnormalities of the maternal pelvis– Contracted Inlet– Contracted Midpelvic– Contracted Outlet– Pelvic Fracture– Abnormalities of soft tissues

of the reproductive tract that form an obstacle to fetal descent

Dystocia• Abnormalities of presentation,

position, or development of the fetus– Face Presentation– Brow Presentation– Transverse Lie– Compound Presentation– Persistent Occiput Posterior

Position– Persistent Occiput Transverse

Position– Hydrocephalus– Fetal Abdominal Distension– Shoulder Dystocia

• Complication– Uterine Rupture– Fistula Formation– Pelvic Floor Injury– Post Partum Lower

Extremity Nerve Injury– Perinatal Complication

Incompetent Cervix• Discrete obstetrical entity

characterized by painless cervical dilatation in the second trimester. It can be followed by prolapse and ballooning of membranes into the vagina, and ultimately, expulsion of an immature fetus. Unless effectively treated, this sequence may repeat in future pregnancies.

• Transvaginal sonography to identify cervical incompetence.

• Etiology– Previous trauma to the cervix such as

dilatation and curettage– Conization– Cauterization– Trachelectomy– Exposure to DES in utero

• Evaluation and Treatment– Decrease physical activity and abstain from

intercourse. – Cervical examinations each week or every

2 weeks to assess effacement and dilatation.

– Cerclage

Assisted Vaginal Delivery

Indications for performing an assisted vaginal  delivery

Maternal: ineffective contractions ineffective pushing maternal exhaustion.

Fetal: suspected fetal compromise in the second stage of labour fetal malposition [OT, OP].

Prophylactic shortening of the second stage: maternal intracranial pathology hypertensive problems cardiac disease class III or IV.

Contraindications for performing an instrumental delivery

Fetal position undetermined Fetal head still above the ischial spines Malpositions brow or mento-posterior Known fetal malformations, e.g. neck teratomas Suspected fetal macrosomia in mother with diabetes Previous shoulder dystocia and current fetal size thought to be similar to previous

pregnancy.

Forcep VS Vacuum

Specific situations where forceps delivery is preferred:

where excessive caput is present over the vertex prematurity (gestation less than 34 weeks) face presentation after-coming head of a breech. maternal conditions that preclude pushing e.g. maternal cardiac disease suspected coagulopathy in the fetus.

Specific contraindications for the use of a vacuum extraction:

fetal position undetermined fetal head still above the ischial spines malpresentations such as face or breech inability to achieve a proper application of cup prematurity <34 weeks of gestation suspected fetal bleeding problems assisted delivery under general anaesthesia any contraindication to maternal pushing.

Assisted Vaginal DeliveryComplication• Laceration and Episiotomy• Urinary and Fecal Incontinence• Scalp lacerations and bruising• Subgaleal hematomas,• Cephalohematomas• Intracranial hemorrhage• Neonatal jaundice• Subconjunctival hemorrhage• Clavicular fracture• Shoulder dystocia• Injury of sixth and seventh cranial nerves• Erb palsy• Retinal hemorrhage• Fetal death

Recomendation• The classification of vacuum deliveries should be

the same as that used for forceps deliveries (including station).

• The same indications and contraindications used for forceps deliveries should be applied to vacuum-assisted deliveries.

• The vacuum should not be applied to an unengaged vertex, that is, above 0 station.

• The individual performing or supervising the procedure should be an experienced operator.

• The operator should be willing to abandon the procedure if it does not proceed easily or if the cup dislodges more than three times

Cesarean SectionPrimary Indication• Dystocia• Nonreassuring fetal

heart rate• Abnormal presentation• Unsuccessful trial of

forceps or vacuum• Placenta Previa

Repeated Indication• No VBAC attempt• Failed VBAC• Unsuccessful trial of

forceps or vacuum

Terima Kasih