Normal Labor and DelivNormal Labor and Deliveryery

正常分娩正常分娩

林建华林建华

Labor :Labor :

the process by which the process by which contractions of uterus expel the contractions of uterus expel the fetus.fetus.

Delivery :Delivery :

receive the neonatereceive the neonate

1. definition1. definition

Term pregnancy: 37-42weeks from Term pregnancy: 37-42weeks from LMPLMP

pre-term delivery (labor): 28- <37 pre-term delivery (labor): 28- <37 weeks of gestational ageweeks of gestational age

post-term delivery:post-term delivery: 42 weeks 42 weeks Abortion : <28 weekAbortion : <28 week 85% of women spontaneous labor 85% of women spontaneous labor

and delivery between 37-42 weeks and delivery between 37-42 weeks

2. The four factors for 2. The four factors for laborlabor

Force ( uterine contraction)Force ( uterine contraction) birth canal (bony canal)birth canal (bony canal) fetus fetus

(lie,position ,presentation,weight(lie,position ,presentation,weight))

psychical-factorspsychical-factors

ContractionsContractions

onset, frequency, duration, intensityonset, frequency, duration, intensity increase in frequency and durationincrease in frequency and duration uterus can be felt to harden during uterus can be felt to harden during

contraction contraction lasting about 30-45 secondslasting about 30-45 seconds interval between contractions to be interval between contractions to be

5 min’5 min’ Intensity (slight, middle, heavy)Intensity (slight, middle, heavy) the pain of labor is a characterthe pain of labor is a character

正常曲线 异常曲线正常曲线 异常曲线

Birth canal;Birth canal;

Bony canalBony canal

Soft tissue canal (lower part of Soft tissue canal (lower part of uterus, cervix, vaginauterus, cervix, vagina

Bony pelvisBony pelvis

The planes of pelvisThe planes of pelvis inlet plane (promontory)inlet plane (promontory) mid plane of pelvis (ischia spinemid plane of pelvis (ischia spine

s)s) outlet plane(two intersecting trioutlet plane(two intersecting tri

angles)angles)

fetus (lie, position ,presentation, weifetus (lie, position ,presentation, weight)ght)

Long axis of motherLong axis of mother LOALOA Head downHead down Estimation of fetal weight :2500g - <4Estimation of fetal weight :2500g - <4

000g000g

3. Mechanism of labor3. Mechanism of labor The process of labor and delivery is marked by chThe process of labor and delivery is marked by ch

ange in fetal position in relation to the maternal pange in fetal position in relation to the maternal pelviselvis

EngagementEngagement(BPD decent to a level below the pelvic inlet(BPD decent to a level below the pelvic inletAn occiput below the ischial spines is engaged)An occiput below the ischial spines is engaged) FlexionFlexion DecentDecent Internal rotationInternal rotation ExtensionExtension External rotationExternal rotation

4. Symptoms and signs of 4. Symptoms and signs of the onset of the laborthe onset of the labor

Painful uterine contractionPainful uterine contraction a showa show effacement and dilation of the effacement and dilation of the

cervixcervix rupture of membranesrupture of membranes

The showThe show The mucus plug is expelled from the cervixThe mucus plug is expelled from the cervix mixing with a little bloodmixing with a little blood

the rupture of the membranesthe rupture of the membranes at any time during laborat any time during labor

effacement and dilation of the cervixeffacement and dilation of the cervix to be short,taken up,dilatedto be short,taken up,dilated

The differentiation of The differentiation of laborlabor

in labor:in labor:

spontaneous uterine contractionspontaneous uterine contraction

with progressive dilation of with progressive dilation of the cervixthe cervix

interval < 5 ’interval < 5 ’

lasting >30’’lasting >30’’

intensity is middle or heavyintensity is middle or heavy

False labor:False labor:

5. Three Stages of labor5. Three Stages of labor

The first stage:The first stage: onset of labor to full cervical dilation(10cm)onset of labor to full cervical dilation(10cm) the latent phase ( onest to <3cm, <16h)the latent phase ( onest to <3cm, <16h) the active phase(>3cm to 10cm, <8h)the active phase(>3cm to 10cm, <8h)The second stage:The second stage: 10 cm to the delivery of the infant, <2h10 cm to the delivery of the infant, <2hThe third stage:The third stage: delivery of the infant to delivery of the pladelivery of the infant to delivery of the pla

centa, <30m’centa, <30m’

6. Management of 6. Management of normal labor normal labor

The first stageThe first stage:: education, eating, walking, education, eating, walking, position(sitting, reclining, position(sitting, reclining,

recumbent)recumbent) monitoring of the fetal heart rate ,monitoring of the fetal heart rate , Palpation of cervix Palpation of cervix

( effacement ,dilation) ( effacement ,dilation) uterus contractions (palpation or uterus contractions (palpation or

electronic monitoring)electronic monitoring) Analgesia and anesthesiaAnalgesia and anesthesia

The second stageThe second stage fetal heart ratefetal heart rate maternal conditions:maternal conditions: pulse, blood pressure, respiratory rate , pulse, blood pressure, respiratory rate , temperature, urine output, fluid intake…temperature, urine output, fluid intake… evaluation of progress of laborevaluation of progress of labor station, position of the presenting part, ststation, position of the presenting part, st

atus of membranes, meconium, bloodatus of membranes, meconium, blood

Pushing:Pushing: with the onset of each contraction, with the onset of each contraction,

the mother is encouraged to inhale,the mother is encouraged to inhale,hold her breath, and pushhold her breath, and push

increase in intra-abdominal pressuincrease in intra-abdominal pressurere

aiding in fetal descent through the aiding in fetal descent through the birth cacal.birth cacal.

Head visible on vulval gappingHead visible on vulval gapping Crowning of headCrowning of head Laceration or EpisiotomyLaceration or Episiotomy Delivery of fetusDelivery of fetus Deal with umbilical cordDeal with umbilical cord

the third stage:the third stage:

waiting for up to 30 minwaiting for up to 30 min Separation indication of placenta:Separation indication of placenta:

the fundus changes to a globular shape anthe fundus changes to a globular shape and firm consistencyd firm consistency

A gush of blood appears vaginallyA gush of blood appears vaginally The umbilical cord appears to lengthenThe umbilical cord appears to lengthen

delivery of placenta (spontaneously, manudelivery of placenta (spontaneously, manuallyally

inspection of the birth canalinspection of the birth canal Repair of lacerations or episiotomyRepair of lacerations or episiotomy

Key word and questionsKey word and questions

LaborLabor DeliveryDelivery EngagementEngagement EffacementEffacement What are the four factors in labor and What are the four factors in labor and

delivery?delivery? What is the mechanisms of labor ?What is the mechanisms of labor ? Explain the separation indications of Explain the separation indications of

placenta.placenta.