Labour & Birth Flashcards by Olivia Davies

What causes the onset of labour?

Mechanical - when the uterus is overstretched

Cytokines/Prostaglandins (inflammatory markers that are stretched when the cervix is distally stretched)

How well did you know this?

Not at all

Perfectly

How is the first stage of labour diagnosed?

When there are regular painful contractions and there is progressive cervical dilation from 4cm

How well did you know this?

Not at all

Perfectly

Why should pregnant women not be examined flat?

Risk of postural supine hypotensive syndrome

How well did you know this?

Not at all

Perfectly

What are the 4 components of an obstetric abdominal exam? (Any clinical exam)

Observation
Inspection
Palpation
Auscultation

How well did you know this?

Not at all

Perfectly

What do you look for in the inspection part of obstetric clinical exam?

Abdominal mass
Stigmata of pregnancy (stretch marks)
Surgical scars

How well did you know this?

Not at all

Perfectly

At what week do you start palpation in an obs exam? What are you palpating for?

From 36 weeks

Uterine size

How well did you know this?

Not at all

Perfectly

From what week can the SFH be measured?

24 weeks

How well did you know this?

Not at all

Perfectly

What’s effacement?

Shortening/thinning of the distal part of the cervix during childbirth

How well did you know this?

Not at all

Perfectly

What are the different landmarks for the fundal height at different weeks?

Symphysis pubis at 12 weeks

Umbilicus at 20 weeks

Xiphisternum at 36 weeks

How well did you know this?

Not at all

Perfectly

What’s the difference between foetal, transverse and oblique lie?

Foetal lie =long axis of the foetus and long axis of the uterus are longitudinal to the mothers

Transverse lie = when long axis of the foetus is perpendicular to the mother’s uterus

Oblique lie = long axis of the foetus is 90-180 degrees of the mothers uterus

How well did you know this?

Not at all

Perfectly

What’s the ideal type of lie in foetal presentation?

Longitudinal lie - preferably cephalic presentation

How well did you know this?

Not at all

Perfectly

What’s a cephalic presentation?

When the foetal head (vertex) is situated over the pelvis

How well did you know this?

Not at all

Perfectly

What type of presentation could a transverse/oblique foetal lie result in?

Shoulder presentation

How well did you know this?

Not at all

Perfectly

What are different types of breech presentation?

Extended or frank = legs up

Flexed or complete = as though baby is sitting

Footling = one or both legs extended at the hip

How well did you know this?

Not at all

Perfectly

When is the foetal head ‘engaged’?

When the widest diameter of the head (biparietal diameter) has passed through the pelvic brim

When 2/5 of the head are palpable at the angle between the head and symphysis pubis

How well did you know this?

Not at all

Perfectly

Why is abdominal palpation of the foetal head assessed in fifths, what does this mean?

Measuring foetal head engagement
3/5 of the head are abdominal palpable = not engaged
2/5 or less = engaged

How well did you know this?

Not at all

Perfectly

What does attitude relate to?

The relationship of the foetal head and limbs to its body:

Fully flexed (ideal)
Deflected
Partially extended
Completely extended

How well did you know this?

Not at all

Perfectly

What should be included in the obs pelvic examination?

Not routinely done

External examination of the vulva
Internal inspection of the vagina and cervix
Vaginal examination if indicated

How well did you know this?

Not at all

Perfectly

How many cm is one finger breadth? How many cm is the 1st stage of labour?

1-1.5 cm = 1 finger breadth

Dilated to 4cm

What’s happening to the cervix during effacement?

Dilates
Length: shortens (from 3cm) as it becomes part of the lower segment of the uterus
Position of cervix becomes more anterior
Consistency becomes softer

The station of presenting part is determined by how much the presenting part has descended into the pelvis (fixed point is ischial spines and can be used)

Position of presentation part: with a cephalic presentation, the anterior and posterior fontanelles and sagittal sutures should be identified

What does station refer to?

Relationship of the presenting part to an imaginary line drawn between the ischial spines of the maternal pelvis

What’s the Bishop score?

Evaluates ‘ripeness’ or favourability of the cervix - the higher the score the more favourable the cervix

How is the progress of labour assessed?

Uterine contractions
Dilation of the cervix
Descent of the presenting part

What’s used to assess progress of labour? How is slow progress indicated?

Partogram

Slow = lack of cervical dilation and failure of descent of the presenting part

What are the 3 stages of labour?

1st stage: onset of regular contractions-> full dilation to 10cm of cervix 2nd stage: full dilation of cervix -> birth of baby 3rd stage: birth of baby -> delivery of placenta, membranes and control of associated bleeding

What stage in labour is the baby born?

2nd stage (once the cervix is fully dilated, at 10cm)

What’s meant by: powers, passage and passenger? (3Ps)

Powers = contractions (strength, length, frequency, effectiveness) Passage = birth canal (bony pelvis, adaptation, soft tissues, pelvic floor, cervix, vagina, vulva) Passenger = size/positioning/coping All 3 interact for successful outcome

What’s the mechanism of delivery in the 1st stage of labour?

Flexion of the head as the cervix is effacing and dilating

What’s the mechanism of delivery during the 2nd stage of labour?

Internal rotation: head reaches pelvic floor, occiput into anterior position Extension: foetal head is delivered under pubic symphysis External rotation: head distends the perineum, allows delivery of the shoulders

What’s induced labour?

Artificial initiation of uterine contractions prior to spontaneous onset

How many women will require induced labour?

1 in 5 deliveries

What are the consequences of induced labour?

Affects birth experience May be less efficient Usually more painful - epidural analgesia required

Why would labour be induced? (Maternal and foetal reasons)

Maternal: severe pre-eclampsia, recurrent antepartum haemorrhage, diabetes Foetal: prolonged pregnancy, IUGR, rhesus disease

What’s Rhesus disease?

Condition where antibodies in pregnant woman’s blood destroy baby’s blood cells (haemolytic disease of the newborn) = anaemic and jaundice

What needs to be assessed for induction?

Favourability of the cervix using Bishop score Favourable cervix = soft, beginning to dilate and efface

What are the main methods or induction?

Prostaglandins eg Dinoprostone by local application (vaginal gel, tablet or pressary) and used to ‘ripen the cervix’ Amniotomy causing local release of endogenous prostaglandins IV induction of synthetic oxytocin (Synctocinon) strength is titrated against strength and frequency of contractions

What’s a risk of prostaglandin (dinoprostone PGE2) use in induction?

Uterine hyperstimulation = 5 contractions in 10 minutes

Why would you intervene operatively in labour?

``` If there’s a delay in 1st or 2nd stage Suspected foetal distress Ante-partum haemorrhage Breech Severe IUGR Twins ``` Maternal reasons: HIV, raised ICP, pre-eclampsia

How is pre-eclampsia diagnosed?

Validated 24 hour urine sample and proteinura >300mg

What can you use in operative interventions in delivery?

Ventouse = cup shaped suction to baby head Forceps Episiotomy = increase diameter of pelvic outlet Caesarean section

What are the 2 ways to monitor the foetus during labour?

Intermittent auscultation using a Picard stethoscope or Doppler Continuous cardiotocographausc monitoring

How often is intermittent auscultation of the foetus during labour done?

Used for all healthy women with non-complicated pregnancies In the 1st stage of labour: for 1 minute immediately after a contractions and at least every 15 minutes In 2nd stage: every 5 minutes and after a contraction

What’s meconium? Meconium aspiration syndrome?

The first stool, blackish green and tenacious (if present in liquor is can be indication of foetal distress) Aspiration of the stained amniotic fluid - causes severe respiratory distress in the newborn, but it’s sterile so can’t cause bacterial pneumonitis

What’s done during the 3rd stage of labour? (There are 2 ways)

Physiological: no drugs, wait for passive delivery of placenta and don’t cut the cord until it stops pulsating Active: use synthetic oxytocin into the thigh, clamp and cut the cord

What can meconium in the amniotic fluid indicate?

Serious disease

What are the advantages of having active management of stage 3 labour?

It shortens the third stage, for anyone who had a distressing labour (previous stages) Associated with a lower risk of blood loss Associated with lower risk of requiring blood transfusion

What are some causes for a 'larger than dates' or smaller measurements of symphysio-fundal height?

Larger: multifetal pregnancy, polyhydramnios and diabetic pregnancy Smaller: intrauterine growth restriction