Labor and Delivery
 

Parturition ROM Cervical Dilation Uterine Contraction Placental separation Uterine Shrinking

Withdrawl of progesterone estrogen  induced uterine activity oxytocin & prostaglandin stimulaton

Braxton Hicks

Stages of Labor and Delivery
			AVERAGE TIME
STAGE	OCCURANCES		PRIMAGRAVIDA	MULTIGRAVIDA
First	Onset of regular contractions to  full (10cm) dilitation and effacement of  the cervix		16-18 hr	7-12 hr
Second	Full dilitation and effacement of the cervix to delivery of the fetus		1 hr (can last up to 2 hr)	20 min
Third	Delivery of the fetus to delivery of the placenta		3-4 min (can last  up to 45 min)	4-5 min

95%vertex
stations above & below ischial spines
tocolysis-terbutaline sulfate, ritodrine, MgSO4 -not indomethicin

• true labor 3 contractions in 20 min.
• cervix <4cm effaced<50%
• 20-36 wks gestation
• no fetal distress
• no disorder contrainicates meds
• informed consent

• uterine dysfunction -hyper or hypotonic
• abnormal fetal presentation -
• breech 3.5%,
• complete
• footling (incomplete)
• frank
• face, brow, shoulder, transverse
• excessive fetal size - cephalopelvic disproportion
• hydrocephalus
• abnormal size or shape of birth canal

Previa
Abruptio- mort mom 2-10% fetus 50%, related to peeclampsia - apparent & concealed hemorrhage -lateral lie for momgraded 0-3

• 2/3 fraternal -
• autosomal recessive in daughters of mothers of twins
• 1/3 identical -random occurance
• high prematurity
• increased congenital anomalies
• growth retardation, bacterial infection, hypoglycemia

Transition to Extra-uterine life
    First breath

1. asphyxia stimulates gasping
2. recoil of thorax draws in air
3. bright loud cold pokey world initiates crying

Circulatory Transition
	Lung inflation  decrease PVR increase PaO2 Ductus Venosis  flow stops- DV constriction Cord Clamped  UA & UV flow stops Ductus Arteriosis  constricts due inc PaO2 Foramen Ovale closes due pressure inc LA Umbilical Arteries constrict & close