Normal labour**

Question 1

during labour there is an interplay of which three factors

Answer 1

power - uterine contraction
passage - maternal pelvis
passenger - fetus

Question 2

progesterone does what

what happens to the levels in labour

Answer 2

keeps the uterus settles and prevents formation of gap junctions and hinders contractibility of myocytes

goes down

Question 3

oestrogen in labour

Answer 3

makes the uterus onctract

promotes prostaglandin production which produces more oestrogen

Question 4

what does oxytocin do in labour

where is it synthesised

what happens to the number of oxytocin receptors

Answer 4

initiates and sustains contractions
acts on decidual tissue to promote prostaglandin release

directly in decidual and extra embryonic metal tissues and in the placenta

increase in myometrial and decidual tissue near the end of the pregnancy

Question 5

how is labour initiated

Answer 5

change in oestrogen/progesterone ratio

fetal adrenals and pit hormones may control timing of onset of labour

myometrial stretch due to uterus getting bigger leads to excitability of myometrial fibres

mechanical stretch of cervix and stripping of metal membranes

fergusons reflex - increase oestrogen and increased prostaglandin release

Question 6

other causes that lead to labour

Answer 6

pulmonary surfactant secreted into amniotic fluid stimulates prostaglandin synthesis

increase in production metal cortisol stimulates an increase in maternal estriol

increase in my-metrical oxytocin receptors and their activation results in phospholipase C activity and subsequent increase in cytosolitic calcium and uterine contraction

Question 7

3 stages of labour consist of what

Answer 7

first - latent/active
second - cervix dilated to 10cm - delivery of baby
third stage - delivery of placenta and membranes

Question 8

latent stage

Answer 8

mild irregular uterine contractions, cervix shortens and softens, duration variable

Question 9

active phase

Answer 9

4cm on to full dilatation
slow descent of the presenting part
contractions progressively becomes more rhythmic and stronger

Question 10

second stage of the labour starts with what
how long does it take
what can happen in low risk px

Answer 10

starts with complete dilatation of the cervix (approx 10cm)

in nulliparous women considered prolonged if it exceeds 3 hours with regional analgesia or 2 hour without

in multiparous women - consider prolonged if it exceeds 2 hours with analgesia or 1 without

in low risk vaginal examinations are not always carried out to assess time for full dilatation

Question 11

what happens during the third stage of labour
time
management actions taken

Answer 11

delivery of the baby to expulsion of the placenta and fatal membranes

av duration 10 mins can be 3 min longer

spontaneous delivery of the placenta - be prepared
use of oxytocin drugs and controlled cord traction is preferred for lowering risk of post partum haemorrhage

Question 12

active management of third stage

Answer 12

syntometrine 1ml ampoule given
or
oxytocin 10 units

cord clamping and cutting
controlled cord traction
bladder emptying

Question 13

cervical softening

Answer 13

increase in hyaluronic acid gives increase in molecules among collagen fibres

decrease in bridging among collagen fibres gives decrease in firmness of cervix

Question 14

cervical ripening

Answer 14

decrease in collagen fibre alignment
decrease in collagen fibre strength
decrease in tensile strength of the cervical matrix
increase in cervical decorin

Question 15

braxton hicks contraction what

when do they start/are felt

Answer 15

tightening of the uterine muscles - thought to aid the body to help prepare for birth
can start 6 weeks into the pregnancy
not usually felt until second or third trimester

irregular, do not increase in frequency or intensity
resolve with ambulation or change in activity
relatively painless

Question 16

true labour contractions feelings

when

Answer 16

like a wave
pain starts low, rises until a peak and then ebbs away
if you touch the mothers abdomen during one it feels hard

start about 5 mins apart

Question 17

what causes true labour contractions

pain

Answer 17

oxytocin causes uterus to contract
evenly spaced
get more intense and painful over time
tighten the top part of the uterus pushing the baby down

Question 18

what do both kinds of contractions do to the cervix

Answer 18

promote thinning of the cervix

Question 19

where is the pacemaker and what direction does the wave spread
how do the waves synchronise
polarity
normal contractions have what

Answer 19

region of tubal ostia, downward direction

both ostia

upper segment contracts and retracts, lower segment and cervix stretch, dilate and relax

fundal dominance with a regular pattern and an adequate resting tone

Question 20

best type of pelvis t have

Answer 20

gynaecoid pelvis

Question 21

anthropoid pelvis

Answer 21

oval shaped inlet with large AP dm and smaller transverse dm

Question 22

android pelvis

who are more at risk of this type of pelvis

Answer 22

triangular or heart shaped inlet and is narrower from the front

african caribbean women

Question 23

what does liquor do

Answer 23

nurtures and protects fetus and facilities movement

Question 24

when does the membrane usually rupture

Answer 24

in the first stage

Question 25

abnormal position

Answer 25

breech, oblique, transverse

occipital posterior

Question 26

crowning of head - what happens

what may be required to prevent trauma to anal sphincters

Answer 26

labia are stretched to full capacity
largest dm of the fatal head is encircles by the vulval ring

episiotomy

Question 27

what are the components of the bishop score

Answer 27

position 
consistency 
effacement 
dilatation 
station in pelvis

Question 28

analgesia in labour

Answer 28

paracetamol/co codamol 
TENS
entonox
diamorphine 
epidural 
remifentanyl 
combined spinal/epidural

Question 29

blood loss normal

abnormal

Answer 29

<500mls normal

>500mls not normal

Question 30

plane of separation of placenta
mechanics of placental separation
method of separation

Answer 30

spongy layer of decidua basalis

shearing force

methew duncan marginal most common type of separation

Question 31

3 signs that indicate placental separation

how long does it take

Answer 31

uterus contracts, hardens and rises
umbilicord cord lengthens permanently
gush of blood variable in amount

5-10 mins after delivery, normal up to 30 mins

Question 32

how is homeostasis achieved

Answer 32

tonic contraction - lattice pattern of uterine muscle strangulates the blood vessels

thrombosis of the torn vessel ends - pregnancy is a hyper coaguable state

myo tamponade opposition of the anterior/posterior walls

Question 33

what is a puerperium

how long does it last

Answer 33

period of repair and recovery

6w

Question 34

what consists of puerperium

Answer 34

return of tissues to non pregnant state 
loch - vaginal discharge containing blood, mucus and endometrial castings 
rubra (fresh blood)
serosa - brownish red watery 
alba - yellow 
uterine involution 
weight reduces 
fundal height - umbilicus within pelvis in 2 weeks 
endometrium regenerates by a week 
diuresis commences 2-3 days post natally

Question 35

physio in puerperium

Answer 35

lactation initiated by placental expulsion
decrease in oestrogen and prog
prolactin is maintained
colostrum rich in immunoglobulin - long term protective effect for the baby