Session 8 - Labour and Delivery

Question 1

What is parturition?

Answer 1

Transition from the pregnant to non-pregnant state.

Question 2

What is labour?

Answer 2

Physiologic process by which a fetus is expelled from the uterus to the outside world.

Question 3

What is delivery?

Answer 3

The method of expulsion of the foetus, transforming the foetus to neonate.

Question 4

Which main things changes occur in labour?

Answer 4

• Dilation of cervix

- Changes in uterine decidua - Uterine contractions.

Question 5

What is the first stage of labour?

Answer 5

Creation of birth canal (and descent of foetal head into it).
(interval between onset of labour and full dilatation of cervix)

Latent: Onset of labour with slow cervical dilatation but softening (variable time)
Active: Faster rate of change, regular contractions.

Question 6

What is the second stage of labour?

Answer 6

• Expulsive contractions of uterus, descent of foetus through birth canal and delivery.
  (Time between full (10cm) dilatation of cervix and delivery.

Passive: Descent, rotation of head.
Active: Maternal effort to expel foetus, achieving birth.

Question 7

What is the third stage of labour?

Answer 7

-Expulsion of placenta and uterine contraction.

after completed birth of baby, until placenta & membranes completely expelled

Question 8

How long does the third stage of labout last?

Answer 8

Usually 5-15 minutes.

30-60 may be normal, depending on circumstances. (longer is not normal)

Question 9

Which important chemicals induce changes required for labour?

Answer 9

• Prostaglandins:
  Cause uterine contractions and ripening of cervix.
• Oxytocin release
  Cause uterine contractions (increase prostaglandins)
  Also causes cervical stimulation (neural reflex)

Question 10

How is labour initiated?

Answer 10

Unclear in humans.

Prostaglandins promote labour.