labor and birth processes

passenger (size/position)
passageway (size)
powers (contractions/pushing)
position of mother
psychologic response

 Size of the fetal head
 Fetal presentation
 Fetal lie
 Fetal attitude
 Fetal position

 Skull bones: 2 frontal, 2 parietal, 2 temporal, 1 occipital
 Sutures: sagittal, frontal, coronal, lambdoid
 Fontanels: anterior, posterior
 Molding: slight overlapping of the bones

sutures - allow molding
may overlap
palpate during SVE after ROM
discover fetal presentation, position, attitude

part that enters pelvis first
cephalic (head) - vertex (occiput)
breech (butt/feet) 3%
shoulder

complete/full - butt/feet same time
frank - thighs flexed on abdomen
incomplete - feet or knees
external version or c-section

spine of fetus to spine of mom
longitudinal/vertical = parallel
transverse/horizontal/oblique = rt. angle diagonal/sideways (no vaginal birth)

relation of body parts to each other - general flexion
vertex = full flexion
sinciput = military attitude
brow = partial extension
face = poor flextion - complete extension

biparietal diameter - side to side
suboccipitobregmatic diameter - front to back
deviations can cause problems

relation of presenting parts of fetus to pelvic quadrant of mother
R/L posterior; R/L anterior
assess with SVE

1st letter - location of presenting part - R/L
2nd letter - name of presenting part (O/S/M/Sc)
3rd letter- location in relation to anterior, posterior, transverse portion of mom's pelvis

relation of fetal presenting part in pelvis - degree of descent
engaged - when at level of ischial spines (0)

bones (ilium, ischium, pubis, & sacral bones)
joints ( Symphasis pubis, the right and left sacroiliac joints, and the sacrococcygeal joint)
false pelvis - above brim
true pelvis (inlet/brim, midpelvis, outlet)

android - male
anthropoid - apelike
gynecoid - classic female
platypelloid - flattened

lower uterine segment
cervix
pelvic floor muscles
vagina
introitus

primary = contractions
secondary = maternal pushing

involuntary
monitor manually or electronically
cause cervix to dilate and efface
descent of fetus

after cervix is completely dilated
causes descent of fetus

 Gravity can promote the descent of the fetus
 Uterine contractions are generally stronger and more efficient in effacing and dilating the cervix
 Resulting in shorter labor
 Beneficial to mother’s cardiac output
 Improve blood flow to the uteroplacental unit and maternal kidneys

 May be used to relieve backache if the fetus is in an occipitoposterior position
 May assist in anterior rotation of the fetus and in cases of shoulder dsytocia

 Lithotomy, semifowler’s, lateral, squatting, hands and knees

 The process of moving the fetus, placenta, and membranes out of the uterus and through the birth canal

 Lightening
 Return of urinary frequency
 Backache
 Stronger Braxton Hicks contractions
 Weight loss: 0.5-1.5 kg
 Surge of energy
 Increased vaginal discharge; bloody show
 Cervical ripening
 Possible rupture of membranes
 Gastrointestinal upsets

 Discharge of mucus plug
 Becomes blood-tinged because of breakage of small cervical capillaries with dilation
 The closer to complete dilation, the more abundant and bloody the show

 Contractions are irregular
 Frequency is usually unchanged
 Duration and intensity are unchanged
 Discomfort is primarily in the abdomen
 Walking does not affect, or may lessen the frequency and intensity
 There is little or no cervical change

 Contractions are regular
 Contractions become more frequent
 Contractions increase in duration and intensity
 Discomfort begins in the lower back and radiates around to the abdomen
 Contractions are usually intensified by walking
 Cervical effacement and dilation are progressive (primary sign)

progressive uterine distension + increased intrauterine pressure + aging placenta
increased conc. of estrogen/prostaglandins, decreased progesterone

protein in plasma and cervicovaginal secretions prior to the onset of labor

 Woman is at or near term
 No complications exist
 A single fetus presents by vertex
 Labor is complete within 18 hours

ourse of normal labor consists of
 Regular progression of uterine contractions
 Progressive effacement and dilation of the cervix
 Progress in descent of the presenting part

regular contractions - full dilation
latent - onset to 3-4 cm dilation
active - 4 cm - 7/8 cm dilation
transition - to 10 cm dilation
7.5 - 13 hours (longest)

full dilation of cervix to birth of fetus
latent - resting
active - contractions resume, bearing down
20-50 minutes

birth of fetus to expulsion of placenta and membranes
3-5 minutes

period of transition, stabilization, recovery
2 hours

cervical dilation and station
determine if labor process is within normal limits

 Head engages to the level of the ischial spines
 Descends and flexes into the pelvis
 Rotates internally to the occiput anterior position
 Moves under the pubic arch and extends to be delivered
 Turns to realign with the back and shoulders (restitution and external rotation)
 Infant is expelled