Normal labour Flashcards
What is labour?
Labour is the process in which the fetus, placenta and membranes are expelled via the birth canal.
When does normal labour occur?
37-42 weeks gestation
What is the normal lie during normal labour?
Vertex
Two key physiological changes must occur to allow for expulsion of the fetus, what are these?
1) Cervix softens
2) Myometrial tone changes to allow for coordinated contractions
3) Progesterone decreases whilst oxytocin and prostaglandins increase to allow for labour to initiate
Which two synthetic hormones can be used to augment and induce labour?
1) Synthetic oxytocin
2) Prostoglandins
What happens in the latent first stage of labour?
A period during which there are intermittent, often irregular, painful contractions which bring about some cervical effacement and dilatation up to 4cm.
What happens in the established first stage of labour?
Regular, painful contractions that result in progressive effacement and cervical dilatation from 4cm.
When is the first stage of labour complete?
When the cervix is fully dilated (10cm)
How long is the average length of established first stage of labour?
8 hours, it is unlikely to last longer than 18 hours
What is the anticipated progress in terms of dilation
0.5 – 1.0 cm dilatation per hour
How do we refer to the size of the cervix?
Fruits: > 1cm-2cm = grape > 3cm = Strawberry > 4cm = Banana > 5cm = Lime > 6cm = Kiwi > 7-8cm = Apple > 9cm = Orange > 10cm = Melon
When does stage II of Labour begin?
When full cervical dilatation (10 cm) has occurred
What does stage II of labour begin ?
From full cervical dilatation to the birth of the baby
What is the Passive second stage of labour?
The finding of full dilatation of the cervix before or in the absence of involuntary expulsive contractions.
Plan to allow one hour of passive second stage to allow for further fetal descent.
What is the Active second stage of labour?
1) The presenting part is visible.
2) Expulsive contractions with a finding of full dilatation of the cervix.
3) Active maternal effort following confirmation of full dilatation of the cervix in the absence of expulsive contractions.
Within primigravida birth, from active stage II of labour when would you expect birth?
Within two hours of active second stage commencing