The document describes the three stages of labour: 1) dilation of the cervix where contractions slowly open the cervix over hours, 2) expulsion where powerful contractions push the baby through the birth canal in minutes to hours, and 3) delivery of the placenta a few minutes after birth. It provides details of the progression and key events of each stage, such as full cervical dilation marking the end of the first stage and clamping of the umbilical cord at the end of the third stage.

1. Birth (Parturition)
Three stages of Labour
1. Dilation of the cervix
2. Stage of Expulsion
3. The Afterbirth
• During the final 3 months, uterus
undergoes weak irregular contractions
• When they are about 30 min apart this
marks the beginning of labour

2. 1st Stage- Dilation of the Cervix
• Onset of labour to complete dilation
• 8-9 hrs (1st child) 4hrs (subsequent children)
• Waves of contractions from top of uterus down
to cervix (like peristalsis)
• With each contraction, muscle fibres of the
uterus shorten and pull on the cervix
• This shortens the cervix until it no longer
protrudes into the vagina, and begins to open
• Dilation allows foetus to move deeper into the
mothers pelvis

3. • Cervix is fully dilated at approx 10 cm
• The uterus, cervix and vagina from a
single curved passage (birth canal)
• Voluntary contractions of the ab. Muscles
aid the uterine contractions
• Full dilation marks the end of this stage

4. 2nd Stage- Stage of Expulsion
• Often begins with breaking of the waters
• Lasts 20 min – 2 hrs
• Contraction of the uterus and abs, push
the foetus through the vagina
• Babies head turns towards woman’s back
• Head advances with contraction and
retracts in between

5. • Mothers pulse increases and she usually breaks
out in a sweat
• Eventually head stretches the vagina and
perineum
• Once emerged the head turns to face the
woman’s hip, this allows the shoulders & body to
pass through the birth canal

6. • As foetus passes through the birth canal
it’s head may be pushed out of shape due
to semi movable joints
• Head resumes normal shape after a few
days

7. • Head first in 90% of births
• Head acts as a wedge
• Foetus may breath before birth is
complete

8. 3rd Stage- The Afterbirth
• Baby is still connected to amnion, chorion and
placenta, which is still in the uterus
• Umbilical is clamped, tied in 2 places and cut
• Arteries & vein retract before or immediately
after the cut
• After a few days the chord dries up and the
navel is left

9. • At birth baby is covered in a waxy material
called Vernix
• Vernix protects the babies skin from
infection ( most removed)

10. • Uterus continues to contract,
approx 5 min later afterbirth
is expelled
• Uterine contractions squeeze
shut uterine blood vessels
minimising blood loss and
blood clots form
• In the past infection was
common
• Expulsion of the afterbirth
can be sped up by
medication