Labour and Birth

Question 1

What catalyses the onset of labour?

Answer 1

1) Thought to be in part mechanical – pre term labour is commonly seen when the uterus is overstretched i.e. multiple pregnancies; polyhydramnios
2) Inflammatory markers such as cytokines and prostagladins play a role (these are present in the decidua and membranes in late pregnancy and are released if the cervix is digitally stretched). Hence a ‘sweep’ is offered as per NICE guidelines to encourage labour.

Question 2

What observations might you find on inspection of an obstetric abdominal exam?

Answer 2

Striae gravidarum - stretch marks
Surgical scars
Fetal movements
Signs of scratching - itching/pruritus

Question 3

What are the 4 parts of palpation in an obstetric abdominal exam?

Answer 3

1) Lie
2) Presentation
3) Position
4) Engagement

Question 4

What is lie?

Answer 4

Lie describes the relationship of the long axis of the fetus to the long axis of the uterus. Can be longitudinal, transverse or oblique.

Question 5

What is presentation?

Answer 5

Presentation refers to the part of the foetus which lies at the pelvic brim or in the lower pole of the uterus.

It can be

• the head (cephalic ) - depending on the degree of flexion or attitude this is either vertex, face or brow
• the breech (either flexed or extended)
• the shoulder

Question 6

What is position?

Answer 6

Can be occipito-anterior, right occipito-anterior, right occipito-transverse, right occipito-posterior, occipito posterior, left occipito posterior, left occipito-transverse, left occipito-anterior

Question 7

What is engagement?

Answer 7

At the start of labour, fetal head will be 5/5 palpable, then 4/5, then 3/5, then 2/5, then 1/5

Question 8

What is station?

Answer 8

Similar to engagement. Is done at the level of the ischial spines. At start of labour, -2, then -1, 0 at the level of the ischial spines, +1, +2 etc. You shouldn’t normally feel the ischial spines in a vaginal exam so just have to imagine it.

Question 9

What is caput?

Answer 9

Caput succedaneum is a diffuse swelling of the scalp caused by the pressure of the scalp against the dilating cervix during labour. It may extend over the midline (as opposed to cephalhaematoma) and is associated with moulding of the head.

Question 10

What is the first stage of labour?

Answer 10

From the onset of regular contractions (with associated dilatation of the cervix) to full dilatation of the woman’s cervix … 10cms

Question 11

What is the second stage of labour?

Answer 11

From full dilatation of the cervix to the birth of the baby

Question 12

What is the third stage of labour?

Answer 12

From the birth of the baby to delivery of the placenta and membranes and control of associated bleeding

Question 13

How does NICE diagnose established 1st stage of labour?

Answer 13

there are regular painful contractions

and

there is progressive cervical dilatation from 4 cm

Question 14

What are the 3 P’s of labour?

Answer 14

Powers - contractions

• strength
• length
• frequency
• effectiveness

Passage - the birth canal

• bony pelvis/adaptations
• soft tissues/pelvic floor
• cervix/vagina/vulva

Passenger - the baby

• size
• positioning
• coping

Question 15

What is cervical ripening?

Answer 15

Ripens or softens during pregnancy and towards term starts to emerge from a normally slightly posterior position to one more central. It also effaces and dilates to allow passage of the fetus

Question 16

What is cervical effacement?

Answer 16

The gradual thinning, shortening and drawing up of the cervix, measured in percentages from 0 to 100%

Question 17

What is cervical dilation?

Answer 17

The gradual opening of the cervix, measured in centimetres from 0 to 10cms.

Question 18

What are the mechanisms of labour?

Answer 18

This describes a pattern of movement undertaken in order that the foetus can traverse the maternal pelvis safely (the passage).

Engagement
Descent
Flexion
Internal rotation
Extension (crowning)
External rotation (restitution)
Expulsion (birth)

(Every Darn Fool in England Eats Raw Eggs)

Question 19

What are some maternal indications for induction?

Answer 19

Severe pre-eclampsia
Recurrent antepartum haemorrahge
Pre-existing disease (e.g.diabetes)
?social reasons

Question 20

What are some fetal indications for induction?

Answer 20

Prolonged pregnancy (most common reason)
Fetal compromise - may be suggested by diminished fetal movements
IUGR - intra uterine growth restriction
Rhesus disease

Question 21

What is a normal fetal heart rate?

Answer 21

110 - 160 bpm

Question 22

What is meconium?

Answer 22

Meconium is the first stool of the newborn, blackish green and tenacious, it should be passed afterrthey are born. The presence of meconium in liquor suggests fetal distress

Question 23

What is active management in the third stage of labour?

Answer 23

Active management involves a combination of early administration of an oxytocic drug (as the shoulders are delivered) and controlled cord traction, see below, once the uterus is well contracted to extract the placenta

Question 24

What is physiological management in the third stage of labour?

Answer 24

Physiological management, on the other, hand as the name implies relies on the woman’s own bodily processes to deliver the placenta and stem any bledding. No drugs are administered and delivery of the placenta occurs passively. The cord is not cut until it stops pulsating’

Question 25

What are the 5 things you should look for on a CTG?

Answer 25

1) Baseline rate (should be 110 - 160 bpm)
2) Baseline variability (should be 5-25)
3) Acceleration
4) No decelerations
5) Uterine contractions

Question 26

How often do you need to listen to the foetal heart during the first stage of labour?

Answer 26

During the first stage use either a Pinard stethoscope or Doppler ultrasound

Carry out intermittent auscultation immediately after a contraction for at least 1 minute, at least every 15 minutes, and record it as a single rate

Question 27

How often do you need to listen to the foetal heart during the second stage of labour?

Answer 27

Perform intermittent auscultation of the fetal heart rate immediately after a contraction for at least 1 minute, at least every 5 minutes. Palpate the woman’s pulse every 15 minutes to differentiate between the two heart rates

Question 28

What are some alternative operative procedures?

Answer 28

• Ventouse delivery (kiwi) - a vaginal extraction with the assistance of a suction cup
• Neville Barnes Forceps - non rotational forceps - often called a ‘lift out’
• Keilland’s forceps - rarely used more invasive rotational forceps
• Caesarian section - an abdominal operative procedure (can be elective or emergency)

Question 29

What are the 4 causes of post-partum haemorrhage?

Answer 29

1) Tone - uterine atony - uterus isn’t contracting
2) Trauma - lacerations of the uterus, cervix or vagina
3) Tissue - retained placenta or tissue or clots
4) Thrombin - pre-existing or acquired