Labour

Question 1

What is oestrogen’s role in labour?

Answer 1

Makes the uterus contract and promotes prostaglandin production

Question 2

What is oxytocin’s role during labour?

Answer 2

Initiates and sustains contractions. It acts on the endometrial lining of the uterus to promote prostaglandin release.

Question 3

What happens to the number of oxytocin receptors towards the end of pregnancy?

Answer 3

The number increases in myometrial and endometrial tissues.

Question 4

How does a cervical sweep help to induce labour?

Answer 4

Sweeping fingers round the cervix catches the membranes around the cervix and promotes prostaglandin release.

Question 5

How is pulmonary surfactant from the foetus involved in labour?

Answer 5

Secreted into amniotic fluid and stimulates prostaglandin synthesis

Question 6

What happens during the first stage of labour?

Answer 6

Latent phase: 3-4cm dilatation, cervix shortens and softens, mild irregular uterine contractions
Active phase: 4cm onwards dilatation, slow descent of the presenting part, contractions become more rhythmic and stronger

Question 7

What happens during the second stage of labour?

Answer 7

Starts with complete dilatation of the cervix -> delivery of baby
Should not extend 3 hours, 2 if multiparous

Question 8

What happens during the third stage of labour?

Answer 8

Delivery of the placenta

On average lasts about 10 minutes

Question 9

Describe True Labour contractions

Answer 9

Feels like a wave - pain starts low and rises until it peaks and then ebbs away. Abdomen will feel hard during a contraction with the fundus the hardest part. They are evenly spaced with the time between getting shorter as labour progresses

Question 10

What is the normal foetal position?

Answer 10

Longitudinal lie, cephalic presentation

Question 11

What is crowning?

Answer 11

Appearance of a large segment of foetal head at the opening of the vagina

Question 12

What are the five elements that make up the Bishop Score?

Answer 12

Position of cervix
Consistency
Effacement - thinning of cervix
Dilatation
Station - in relation to ischial spines

Question 13

What is the normal amount of blood loss during pregnancy?

Answer 13

Volume less than 500mls

Question 14

What are the two methods of placental separation?

Answer 14

Matthew Duncan: most common; marginal separation

Schultz: separation from central aspect

Question 15

How long after birth is normal for placental delivery?

Answer 15

Normally takes 5-10 minutes

Up to 30 minutes is considered normal.

Question 16

What is etonox?

Answer 16

“gas and air”
50% nitrous oxide
50% oxygen
Used as an analgesic

Question 17

What is TENS? And where is it administered?

Answer 17

Transcutaneous electrical nerve stimulation
Analgesic effect
Administered T10-L1, S2-4

Question 18

What is the normal baseline heartrate for the foetus?

Answer 18

100-160bpm

Question 19

What is the normal baseline variability that should be seen on CTG for the foetus?

Answer 19

5 or more bpm

Question 20

When would tocolysis be given?

Answer 20

In premature labour situations. Suppresses uterine contractions.

Question 21

Which position can the mother be put in to prevent vena cava compression?

Answer 21

Lie mother on left side.

Question 22

What is the normal range for pH foetal blood sampling?

Answer 22

> 7.25

If reached below 7.2 then want to deliver the baby immediately - baby acidotic

Question 23

What is classed as a term pregnancy?

Answer 23

27-42 weeks

Question 24

During labour how often are contractions? (i.e. what is normal on a CTG)

Answer 24

4 contractions every 10 minutes

Should last about 1 minute

Question 25

What causes baseline tachycardia in the foetus?

Answer 25

Maternal infection, increased foetal movements, severe hypoxia, hyperthyroidism, maternal/foetal anaemia

Question 26

What causes baseline bradycardia in the foetus?

Answer 26

normal in post-dates foetus, epidurals, congenital heart defects.

Question 27

What can cause reduced foetal baseline variability?

Answer 27

Foetal sleeping, foetal acidosis (from hypoxia), drugs (opiates, benzos), CHD

Question 28

What is an acceleration on a CTG?

Answer 28

A >15bpm increase in the baseline heart rate for 15 seconds - reassuring alongside uterine contractions.

Question 29

Describe a variable deceleration on a CTG

Answer 29

Rapid all from baseline with a variable recovery phase. Usually caused by compression of the umbilical cord and so can resolve if the mother changes position