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Flashcards in embryology birth Deck (19):

definition of a normal birth

  • the baby is born after a period of pregnancy of 259-293 days
  • labour has a duration between 3 and 18 hours
  • the baby is born with its head in face-up position rotating to face-down position


  • the amniotic sac breaks during the contractions
  • blood loss of the mother is no more than 500ml
  • mother and baby are not considerably endangered


Signs for an approaching delivery

  1. periodic contractions (intervals < 10 min.)
  2. loss of amniotic fluid
  3. vaginal bleeding


Trigger for contractions

Trigger: Protein

origin: in the lungs of the baby


Trigger: release of hormone oxytocin

Origin: placenta


Initiation of birth


hormone oxytocin

responsible for loyality to your partner, makes us feel physically connected to each other

breastfeeding mother & child

oxytocin = high (-> chance of cheating is lower)


First stage

1. Contractions

Duration: 15-20h

Wehen= muscle contractions of the uterine muscle

After each contraction the musclefibres of the uterus do not fully return to their original length, but stay a bit shortened. -> The uterus wall is pulled over the head of the baby


Result of this process: cervix opened up to a max of 10cm


2. Stage

2. Descent and delivery of the infant

Duration: several minutes up to one hour

  • this stage begins when the cevix is fully dilated
  • Distance between p and s: 11cm
  • Hormonal influence leads to: softening of the public bone
  • Coccyx: Can be moved 2cm
  • The baby is pressed from the uterine and abdomal muscle out of the birth canal head first; pressure may reach a level of 20 kPa
  • When passing the birth canal, the child is performing a helical rotation into a face-down position.





can be moved for 2cm


Where to deliver a baby

  • at home (with midwife)
  • delivery room


How to deliver

  • lying on the back (supine)
  • in the water
  • standing


3. Stage

3. Delivery of the placenta

Duration: 15 min up to one hour...

-> until the placenta is completely delivered

After delivery: mother is to be observed for another 2h

=> the process of labour is now offically finished


Complications of birth:


Longitudinal position (99,5%): Normal delivery

Transverse position (0,5%): Vaginal delivery is not possible



Complications of birth:

Size of birth canal

The canal's diameter is too small for the cranum of the baby. Vaginal delivery will not be possible.


Complications of birth:

Umbilical cord prolapse (0,14-0,62%)

The fetus moves downward into the pelvis and puts pressure on the cord.. As a result, oxygen and blood supplies to the fetus are diminished or cut-off and the baby must be delivered quickly.

Immediate consequence: lock of oxygen

Lasting effects on the child: brain damage


Complications of birth:

placental abruption (1%)

Placental lining has separated from the uterus of the mother too early

Lasting effects on the child: lack of O2 -> brain damage

Lasting effects on the mother: loss of blood, severe case of shock (can cause death)


Solutions for a successful birth in case of complications:


1. episiotomy (Dammschnitt)

This procedure is necessary when the tissue of the perinaeum cannot expand enough for the head of the baby to pass through without rupture


Solutions for a successful birth in case of complications


2. Caesarean section

This procedure is the safest way of birth when a vaginal birth is risky or impossible. In Switzerland 15-20% of all babys are delivered this way.


Where and how is the section made?

Nowdays: Transverse cut just above the edge of the genital hair



patient controlled analgesia

(the more it is used the more the woman's body is getting used to it)



peridural analgesia