Stages of Childbirth Flashcards
The first stage occurs from ________ until _______
Onset of labour (true contractions)
10cm cervical dilatation
The second stage occurs from _______ until _______
10cm cervical dilatation
Delivery of the baby
The third stage occurs from _______ until _______
Delivery of the baby
Delivery of the placenta
What are Braxton-Hicks contractions?
When do they usually occur?
Occasional irregular contractions of the uterus. Not true contractions and DO NOT INDICATE ONSET OF LABOUR!
Usually felt in the 2nd and 3rd trimester.
What is the management for Braxton-Hicks contractions?
Staying hydrated and relaxing
No medicine needed
What is effacement and when does it occur?
Cervix stretching and getting thinner
Occurs in 1st stage of labour
What is the “show”?
When does it fall out?
Mucus plug in the cervix that prevents bacteria from entering uterus during pregnancy.
Falls out in 1st stage to create space for baby to pass through.
What are the 3 phases of the first stage?
LAT
- Latent phase
- Active phase
- Transition phase
What occurs in the latent phase of the first stage of labour?
Cervical dilation 0.5cm/hr
0 –> 3cm dilatation
Irregular PAINFUL contractions
What occurs in the active phase of the first stage of labour?
Cervical dilation 1cm/hr
3 –> 7cm dilatation
Regular contractions
What occurs in the transition phase of the first stage of labour?
Cervical dilation 1cm/hr
7 –> 10cm dilatation
Strong and regular contractions
What are the 3 P’s of the second stage?
Hint: these are critical to the success of delivery of the baby.
Power
Passenger
Passage
What is POWER in the second stage?
Strength of the uterine contractions
What is PASSENGER in the second stage? (Hint: 4 qualities)
SLAP
Size: size of head
Lie: position of foetus
compared to mother’s body
Attitude: posture of fetus (back rounded? head/limbs flexed?)
Presentation: Cephalic/shoulder/Breech
What is PASSAGE in the second stage?
Size and shape of the passageway, mainly pelvis
What are the 7 cardinal movements of labour?
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- Restitution and external rotation
- Expulsion
What is descent in labour?
Position of baby’s head in relation to mother’s ischial spines during descent phase.
How is descent measured in labour?
Hint: There are 3 landmarks
- 5cm: baby high up at round pelvic inlet
0cm: head is at ischial spines (ENGAGED)
+5cm: when fetal head has descended further out
What is physiological management of the third stage of labour?
Placenta delivered by maternal effort without meds or cord traction.
What is active management of the third stage of labour?
Midwife/doctor assist in delivering placenta.
Why is active management of the third stage of labour carried out?
Shortens 3rd stage and reduces bleeding risk
Done if haemorrhage or 60 min+ delay in delivering the placenta
What drug is primarily used during active management of labour?
IM oxytocin to help uterus contract and expel the placenta
Done together with careful traction of umblical cord to guide it out of uterus and vagina.
What are the 4 signs of labour?
Show (mucus plug from cervix)
ROM
Regular,painful contractions
Dilating cervix on examination
When is induction of labour used?
- When patients go over due date (41-42 weeks gestation)
or
When beneficial to start labour early:
- Prelabour ROM
- FGR
- Pre-eclampsia
- Obstetric cholestasis
- Existing diabetes
- Miscarriage
What is the Bishop score?
Scoring system used to determine whether to induce labour
Assesses 5 things: fetal station, cervical positon, cervical dilatation, cervical effacement and cervical consistency.
Score 8+ = predicts successful induction of
labour
Score below this = cervical ripening may be required to prepare the cervix
What are options for the induction of labour? (List 5)
Membrane sweep
Vaginal prostaglandin E2
Cervical ripening balloon (CRB)
Artifical ROM with oxytocin infusion
Oral mifepristone + misoprostol
When is membrane sweet performed?
40 weeks gestation+ to initiate labour in women over EDD
Labour induced within 48 hours!
What forms can vaginal prostaglandin be given in?
Pessary
Gel
Tablet
Done in hospital so woman can be observed before being let home.
What is the role of prostagladins in labour?
Stimulates cervix and uterus to cause onset of labour.
When are CRB and artificial ROM used?
To induce labour when vaginal prostagladins are contraindicated or failed.
When is oral mifepristone + misoprostol used?
To induce labour where intrauterine fetal death has occured. - Miscarriage :(
What 2 monitoring forms are used during induction of labour?
CTG (fetal HR and uterine contractions before/during induction of labour)
Bishop score (before and during induction to monitor progress)
What is the main complication of inducing labour with vaginal prostaglandins?
Uterine hyperstimulation
*Uterus contracts prolonged and frequent - causes fetal distress and compromise
What are the 2 criteria for uterine hyperstimulation?
Individual uterine contractions lasting more than 2 minutes in duration
More than 5 uterine contractions every 10 minutes
What are the risks of uterine hyperstimulation?
Fetal compromise (hypoxia/acidosis)
Emergency C-section
Uterine rupture
How is uterine hyperstimulation managed?
Removing vaginal prostaglandins or stopping oxytocin infusion (stop medications causing contractions for labour)
Tocolysis with terbutaline (stop contractions)
When does a perineal tear occur?
When external vaginal opening is too narrow to accommodate the baby.
Baby’s head passes and tears through.
How are perineal tears classified?
Frenulum of labia minora and superficial skin (1st degree)
Perineal mucles (2nd degree)
Large tear involving anal sphincter (3rd degree)
Large tear involving rectal mucosa (4th degree)
What are risk factors for perineal tears?
First births (nulliparity) Large babies (over 4kg) Shoulder dystocia Asian ethnicity Occipito-posterior position of fetus Instrument delivery
How are perineal tears managed?
Depends on their degree.
First degree - no sutures
2+ degree - sutures + the following:
- Broad spectrum abx to reduce infection
- Laxatives to reduce constipation and wound dehiscence
- Physio to reduce incontinence
- Followup to monitor for longstanding complications
Women symptomatic after 3rd/4th degree tears are offered elective C-section in subsequent pregnancies.
What are short term complications after repair of perineal tears?
Pain
Infection
Bleeding
Wound dehiscence/breakdown
What are long-term complications of perineal tears?
Urine/faecal incontinence
Painful sex
Psych/mental health
Fistula between vagina/bowel (rare)
Why is an episiotomy sometimes performed?
Cut in perineum
Done when anticipating more room for delivering baby
Avoids damaging the anal sphincter in a perineal tear
Cut is sutured after delivery
Why is a perineal massage sometimes perfomed?
Done in advance of delivery to stretch and prepare the tissues for delivery.
How much blood needs to be lost to be classified as a postpartum hemorrhage?
500ml (if vaginal delivery)
1000ml (after C-section)
What are the 4 grades of postpartum hemorrhage?
Minor PPH <1000ml loss
Major PPH >1000ml loss
Moderate PPH 1000-2000 loss
Severe PPH >2000ml loss
What is the difference between primary and secondary postpartum hemorrhage?
Primary PPH - bleeding within 24h of birth
Secondary PPH - bleeding from 24h - 12 weeks after birth
What are the 4 causes of postpartum hemorrhage?
Hint: 4 T’s
Tone - uterine atony
Trauma - perineal tear
Tissue - retained placenta
Thrombin - bleeding disorder
What are risk factors for postpartum hemorrhage?
Previous PPH Multiple pregnancy Obesity Large baby Failure to progress in second stage of labour Prolonged third stage Pre-eclampsia Placenta accreta Retained placenta Instrumental delivery General anaesthesia Episiotomy or perineal tear
What are preventative measures against postpartum hemorrhage?
Treating anaemia antenatally
Giving birth with empty bladder (full bladder reduces uterine contraction)
Active management of 3rd stage (with IM oxytocin)
IV tranexamic acid (during C-section in 3rd stage in higher risk patients)
List the management steps for postpartum hemorrhage.
MDT approach
ABCDE resuscitation
Lie woman flat, keep warm and communicate
Insert 2x large cannulas
Bloods - FBC, U&E, Clotting
Group+cross match 4 units blood
Warmed IV fluid and blood as required
Oxygen (regardless of saturations)
FFP when clotting abnormalities or after 4 units of blood
What blood group can be used instead of crossmatched blood/
O negative
What are MECHANICAL treatment options for stopping the bleeding with postpartum hemorrhage?
Rubbing uterus (stimulates contraction)
Catherisation (bladder distension prevents uterus contractions)
What are possible sources of bleeding for postpartum hemorrhage?
Uterine rupture High vaginal tear Cervical tear Perineal trauma Retained placenta
Usually atonic uterus is the cause or fails to contract properly.
When is an atonic uterus more common?
During prolonged labour
Grand multiparity
OVerdistension of uterus (polyhydramnios, multiple pregnancy)
What are MEDICAL treatment options for stopping the bleeding with postpartum hemorrhage?
Oxytocin (IM + IV infusion) - stimulates uterus contraction
Ergometrine (IV/IM) - stimulates smooth muscle contraction. Don’t use if HTN.
Carboprost (IM) - prostagladin analogue - stimulates uterus contraction. Don’t use if asthma.
Misoprostol (SL) - prostagladin analogue - stimulates uterus contraction.
Tranexamic acid (IV) - antifibrinolytic reduces bleeding
What are SURGICAL treatment options for stopping the bleeding with postpartum hemorrhage?
Intrauterine balloon tamponade (presses against bleeding)
B-Lynch suture (around uterus, compresses it)
Uterine artery ligation
Hysterectomy (last resort, only to save woman’s life)
What is likely to cause secondary postpartum hemorrhage?
Retained placenta
Infection (endometritis)
What are investigations that can be done for secondary postpartum hemorrhage?
USS for retained placenta
Endocervical/high vaginal swabs for infection
How is secondary postpartum hemorrhage managed?
Depends on cause
Surgical input - retained placenta
Antibiotics - infection
What is cord prolapse?
Umbilical cord goes below presenting part of the fetus –> through cervix —> into vagina
Happens after ROM
What is the most dangerous complication of cord prolapse?
Fetal hypoxia due to cord being compressed
*cord compression due to presenting part of the fetus pressing on the cord
What is the most significant risk factor for cord prolapse?
Abnormal lie after 37 weeks gestation (unstable, transverse, oblique)
How is umbilical cord prolapse diagnosed?
Signs of fetal distress on CTG
Vaginal speculum examination
How is umbilical cord prolapse managed?
Emergency C-section
Left-lateral position or knee-chest position (all 4s) to draw fetus away from pelvis and reduce cord compression
Tocolysis (terbutaline) to minimise contractions while waiting for C-section
What is the role of oxytocin in labour and delivery?
Ripens cervix
Causes uterus contractions
*Also role in lactation during breastfeeding
Induce/progress labour
Prevent/treat PPH
Where is oxytocin secreted?
Posterior pitutary gland
*Produced in the hypothalamus first
What is atosiban and when can it be used?
Oxytocin receptor antagonist
Used as alternative to nifedipine in tocolysis in premature labour when nifedipine is contraindicated.
What is ergometrine used for?
Reduce/treat PPH when delivering placenta
- Used only AFTER delivery of baby (3rd stage)
- Works by stimulating smooth muscle contraction in uterus and blood vessels
What is the role of prostaglandins in labour and delivery?
Stimulating contraction of uterine muscles
Ripening cervix before delivery
*Also involved in menstruation - contracting uterine muscles
Which specific prostaglandin is used for the induction of labour?
What are the 3 forms?
Prostaglandin E2
Pessary, tablets, gel
What is the effect of prostaglandins on blood vessels?
Vasodilators
Reduce BP
*NSAIDs work antagonistically so increase BP
What is misoprostol and what is it used for?
Prostaglandin analogue
Binds prostagladin receptors and activates them
Inducing labour after intrauterine fetal death
Abortions
*Hint: Miso = Misery
What is nifedipine and what is it used for in pregnancy?
Calcium channel blocker
- Reduce BP in HTN and pre-eclampsia
- Tocolysis in premature labour - suppresses uterine contractions and delays onset of labour
What is terbutaline and what is it used for in pregnancy?
Beta 2 agonist
Acts on smooth muscle of uterus to suppress uterine contractions
Used for tocolysis in uterine hyperstimulation (if contractions +++ during induction of labour)
What is carboprost and what is it used for?
Synthetic prostaglandin analogue
Stimulates uterine contraction
Deep IM injection to stop PPH *used when ergometrine/oxytocin unsuccessful
*Can cause life-threatening complication with asthma
What is tranexamic acid and what is it used for in pregnancy?
Antifibrinolytic (binds plasminogen and prevents conversion to plasmin)
Plasmin = breaks down fibrin blood clots
Prevention + treatment of PPH
