Parturition - Normal Birth

Question 1

What are the three P’s of labour?

Answer 1

• Passage
• Power
• Passenger

Question 2

What are the challenges in human parturition?

• Quiescence
• Timing
• Activation
• Birth
• Involution

Answer 2

• Quiescence of uterus with growth, distension, pressure
• Timing for safe birth
• Activation of uterine musculature, changes in genital tract
• Birth - foetal/neonatal adaptations
• Involution - haemostasis and establishing lactation

Question 3

____ helps maintain the uterus in a state of quiescence

Answer 3

Progesterone

Question 4

Gestational length ____ with parity and age

Answer 4

Decreases

Question 5

Labour usually occurs ___ days from LMP

Answer 5

280 days

Question 6

What myometrial changes occur in activation?

Answer 6

• Increase in CAPs - gap junctions
• Prostaglandin receptors
• Oxytocin receptors

Question 7

What is the most common CAP in myometrial up-regulation?

Answer 7

Connexin 43

Question 8

Actin/myosin cause ____ myometrial contractility and are antagonised with ____ channel blockers

Answer 8

Increased

Calcium

Question 9

Ca2+ voltage channels cause ____ myocyte excitability and are clinically blocked with _____

Answer 9

Increased

B2 sympathomimetics

Question 10

Gap junctions caused ____ intercellular connectivity and are antagonised with _____

Answer 10

Increased

PG synthase inhibitors (COX1 and COX2)

Question 11

Though serum progesterone levels do not change prior to labour, the ratio and activity of the progesterone _____ in the uterus change such that there is effectively a _____

Answer 11

Receptors

Progesterone withdrawal

Question 12

The increase in ______ in the myometrium is a prerequisite for synchronous uterine contractions towards term or in the preterm situation.

Answer 12

Gap junctions

Question 13

B-adrenergic agonists cause myometrial ____ by binding to adenyl cyclase linked receptors

Answer 13

Relaxation

Question 14

What 3 effects do prostaglandins have on labour?

Answer 14

• Increase myometrial contractility
• Lead to cervix changes
• Associated with membrane rupture

Question 15

Prostaglandin analogues can be used in induction of ____ and cervical ____

Answer 15

Labour

Priming

Question 16

What is the use of oxytocin in post-partum haemorrhage?

Answer 16

• Potent drug to cause contraction of uterus

- Used to prevent post-partum haemorrhage

Question 17

Cervical ripening involves the complete ____ of the ECM

Answer 17

Degradation

Question 18

The area between the chorion and the decidua is the site of _____ production

Answer 18

Prostaglandin

Question 19

Foetal membrane rupture occurs at the ______

Answer 19

Zone of altered morphology

Question 20

What are the three stages of labour?

Answer 20

1. Until full dilatation (10cm)
2. Full dilatation until birth of baby
3. Birth of baby to delivery of placenta

Question 21

The cervix usually dilates at a rate of ___cm per hour

Answer 21

1

Question 22

During the ___ component of a contraction there is no intervillous blood flow

Answer 22

Pain

Question 23

What changes must occur in the nenoate at birth?

Answer 23

• Establishing continuous breathing
• Cardiovascular adaptations
• Thermogenesis
• Intermittent nutrition

Question 24

What uterine changes occur in involution?

Answer 24

• Placental separation
• Cleavage through decidua basalis
• Contractions to prevent postpartum haemorrhage
• Increased uterine sensitivity to oxytocin

Question 25

Term neonates can maintain body temp to ambient 23 degrees for ___ mins

Answer 25

30-60

Question 26

How do you avoid evaporative heat loss in a neonate?

Answer 26

Dry the baby

Question 27

What intervention can help to reduce neonatal encephalopathy?

Answer 27

Head cooling