Labour and Birth Flashcards
oxytocin role in initiation of labour
number of oxytocin receptors in the uterus increases at the end of pregnancy. This creates an increased sensitivity to oxytocin (released from posterior pituitary)
explain change in estrogen to progesterone ration in initiating pregnancy
- During the last trimester of pregnancy, estrogen levels increase, and progesterone levels decrease.
- This change leads to an increase in the number of myometrium gap junctions. Gap junctions are proteins that connect cell membranes and facilitate coordination of uterine contractions and myometrial stretching.
prostaglandins role in initiation of labour
lead to additional contractions, cervical softening, gap junction induction, and myometrial sensitization, thereby leading to a progressive cervical dilation
progesterone may be given to pts who go into labour early because
it helps suppress uterine contractions
2 main functions of uterine contractions
(1) to dilate the cervix and
(2) to push the fetus through the birth canal
cervical changes before labour
cervical softening and possible dilation with descent of the presenting part into the pelvis occur
softening and dilation of cervix can occur ________ to _______ before actual labour begins
1 month to 1 hour
what is essential for effacement and dilation of cervix
ripening and softening of the cervix
lightening occurs when
the fetal presenting part begins to descend into the true pelvis
during lightening the uterus depresses and moves into a more ___________ position
anterior position
increased energy level before labour is referred to as
nesting
during pregnancy the mucous plug fills
the cervical canal during pregnancy
at onset of labour or before the mucous plug is expelled as a result of
cervical softening and increased pressure of the presenting part
the mucous plug being expelled results in the release of
a small amount of blood that mixes with mucous resulting in pink-tinged secretions
characteristics of braxton hicks contractions
- lasting as little as 30 sec or persisting as long as 2 minutes
why do braxton hicks contractions occur
As birth get closer the uterus becomes more sensitive to oxytocin
braxton hicks aid in moving the cervix from a
posterior to an anterior position
braxton hicks also help in ____________ the cervix
ripening
although much of the amniotic fluid is lost when rupture of membranes occurs a continuous supply is produced to ensure
protection of fetus at birth
five P’s of labour
powers
passageway
passenger
position
psyche
powers of labour include the
contractions
two types of contractions
false and true
false labour
- occurs in latter weeks of some pregnancies in which irregular uterine contractions are felt but the cervix is not affected
- False labour, prodromal labour, and Braxton hicks are all names for contractions that do no cause a measurable change in the cervix
true labour
- Characterized by contractions occurring at regular intervals that increase in frequency, duration, and intensity
- True labour contractions bring about cervical dilation and effacement
- Contractions will continue with rest and activity
characteristics of contractions
increment, acme, decrement
increment of contractions is the
building up of the contraction
acme of contractions is the
strongest, top portion of contraction
decrement of contractions is the
rapid diminishing of contraction
abdominal muscles are the ________ _______ in labour
secondary powers
abdominal muscles in labour involve the use of
intra-abdominal pressure (voluntary muscle contractions) exerted by the client when pushing and bearing down during the second stage of labour
when assessing contractions we want to assess the
frequency
duration
intensity
relaxation
how long is frequency of contractions assessed
assess for at least ten minutes
how is duration of contractions assessed
beginning of one contraction to end of same contractions
how is intensity of contractions assessed
palpate at fundus
mild feels like tip of nose
moderate feels like chin
severe feels like forehead
what is tachysystole
– when not enough relaxation between contractions
how is tachysystole characterized
More than 5 contractions in 10 mins, can be contractions lasting longer than 90 secs, resting tone of less than 30 seconds
the passage way or brith canal consists of _______ and ______
bony pelvis and soft tissues
_________ is considered the true female pelvis
gynecoid
3 planes of pelvis
inlet, mid pelvis, outlet
inlet of the pelvis is
entrance from false pelvis to true pelvis
mid pelvis is the
space between the inlet and outlet, fetus must travel through this to reach the outside
outlet of the pelvis is
where fetus passes through to get to the outside
soft tissue factors of passageway include the
cervix, pelvic floor muscles, and the vagina
characteristics of cervix in the passageway
Through effacement the cervix effaces (thins) to allow the presenting fetal part to descend into the vagina
characteristics of pelvic floor muscles in the passageway
Pelvic floor muscles help the fetus to rotate anteriorly as it passes through the birth canal
characteristics of vagina in passageway
Soft tissue of vagina expand to accommodate the fetus during birth
in passenger of labour we consider the fetal
head, attitude, lie, presentation, position, station, and engagement, attitude
importance of sutures in fetal head
they allow the cranial bones to overlap in order for the head to adjust in shape (elongate) when pressure is exerted on it by uterine contractions or the bony pelvis
most common fetal attitude when labour begins
The most common fetal attitude when labour begins is with all joints flexed
fetal lie refers to the
the relationship of the long axis (spine) of the fetus to the long axis (spine) of the pregnant person
fetal station refers to
relationship of the presenting part to the level of the pelvic ischial spines
fetal engagement signifies the
entrance of the largest diameter of the fetal presenting part (usually the fetal head) into the smallest diameter of the pelvis
fetal presentation
the body part of the fetus that enters the pelvic inlet first (the “presenting part”)
by term, approx 97% of infants actively turn to a ___________ presentation
cephalic
fetal position describes the
relationship of a given point on the presenting part of the fetus to a designated point of the pelvis
non-breech fetal positions
1) Left occiput posterior (LOP)
2) Left occiput transverse (LOT)
3) Left occiput anterior (LOA)
4) Right occiput posterior (ROP)
5) Right occiput transverse (ROT)
6) Right occiput anterior (ROA)
The use of any upright or lateral position, compared with supine or lithotomy positions, may
- Reduce the length of the first stage of labour
- Reduce the duration of the second stage of labour
- Reduce the number of assisted deliveries (vacuum and forceps)
- Reduce the incidence of episiotomies and perineal tears
- Contribute to fewer abnormal fetal heart rate patterns
- Increase comfort/reduce requests for pain medication
- Enhance a sense of control by the mother
- Alter the shape and size of the pelvis, which assists in descent
- Assist gravity to move the fetus downward
the state of mind throughout the labor and birth process is critical to bringing
a positive outcome
additional P’s in labour
1) Philosophy – low tech, high touch
2) Partners – support caregivers
3) Patience – natural timing
4) Patient preparation – childbirth knowledge base
5) Pain management – comfort measures
there are _____ stages of labour
4
the first stage of labour has 3 phases:
latent phase
active phase
transition phase
latent phase
- 0-3 cm
- Contractions mild and short (30 – 45 sec) Q5-10 minutes
- Cervical effacement from 0% to 40%
active phase
- 4-7 cm
- Contractions stronger (40 – 60 sec) Q2-5 minutes
- Cervical effacement from 40% to 80%
transition phase
- 8-10 cm
- Contraction at peak intensity (60 – 90 sec) Q1-2 minutes
- Cervical effacement from 80% to 100%
second stage has two phase the
pelvic phase and the perineal phase
pelvic phase
Period of fetal descent
perineal phase
- Phase of active pushing
- Contraction lasting 60 – 90 sec Q2-3 minutes or less
- Strong urge to push during the later perineal phase
third stage includes
placental separation and placental expulsion
placental separation is the
Detaching from uterine wall
placental expulsion is the
Coming outside the vaginal opening
fourth stage
- Pts body begins to stabilize after the hard work of labour and loss of products of conception
- Sometimes not recognized as a true stage but is critical period for physiologic transition as well as new family attachment
- Close monitoring of both mom and baby are essential during this stage
not admitted until in _______ labour at ___cm dilated
active labour at 4 cm dilated
questions to ask during admission when going into labour
- Labour?
- Due date?
- GTPAL?
- Membranes?
- Blood show?
- Fetal activity?
- History?
assessment during labor
- Review prenatal history
- Urine specimen
- Temp, HR, BP, FHR
- Address presenting history
- Vaginal exam (RN or MD)
Birth sequence form crowning through birth of the newborn
A. Early crowning of the fetal head. Notice the bulging of the perineum.
B. Late crowning. Notice that the fetal head is appearing face down. This is the normal OA position.
C. As the head extends, you can see that the occiput is to the client’s right side—ROA position.
D. The cardinal movement of extension.
E. The shoulders are born. Notice how the head has turned to line up with the shoulders; the cardinal movement of external rotation.
F. The body easily follows the shoulders.
G. The newborn is held for the first time.
4 parts of Leopold’s maneuvers
uterine fundus
fetal orientation
fetal presentation
degree of descent
Leopold’s maneuvers: uterine fundus
What fetal part (head or buttocks) is at the fundus
o Head: round, more mobile
o Breech: larger, nodular mass
Leopold’s maneuvers: fetal orientation
Palpate and support down the side of the abdomen
o One side will feel soft – that’s the back; if smooth side on left then baby’s on left and vice versa
o Other side will feel bumpy – that’s the legs, feet, arms
