Labour and delivery Flashcards
When do labour and delivery normally occur during pregnancy?
Between 37 and 42 weeks gestation
When is labour diagnosed
when painful uterine contractions accompany dilatation and effacement (thinning/shortening) of the cervix
What is the 1st stage of labour
From the onset of true labour to when the cervix is fully dilated
What is the 2nd Stage of labour?
From full dilation of the cervix to the delivery of the baby
What is 3rd stage of labour?
From the delivery of the baby to delivery of the placenta and membranes
Give 4 signs of labour
- regular and painful uterine contractions
- a show (shedding of mucous plug)
- spontaneous rupture of the membranes (not always)
- shortening and dilation of the cervix
What are the phases of Stage 1 of labour and their characteristics?
- Latent phase: 0-3cm cervical dilation. Irregular contractions, effacement of cervix
- active (established first stage) phase: 4-10 cm cervical dilation, regular, painful contractions
What are Braxton-Hicks contractions, and how do they differ from true contractions?
Braxton-Hicks contractions are occasional irregular contractions of the uterus that are not true contractions. They do not indicate the onset of labour and do not progress or become regular.
Describe the two stages within stage 2 labour
- passive - full dilatation until the head reaches pelvic floor
- active - when the mother is pushing
What are the three factors that influence progress in labour?
- Power - uterine contractions
- Passenger - size, presentation, lie and attitude
- Passage - shape and size of the pelvis and soft tissues
What is the average cervical dilation rate during the active first stage of labour for nulliparous and multiparous women?
- nulliparous women - 1 cm/hr
- multiparous women - around 2 cm/hr
What constitutes a delay in the first stage of labour?
either:
* less than 2 cm of cervical dilation in 4 hours
* slowing of progress in a multiparous woman.
What tool is used to monitor the progress of women during the first stage of labour?
partogram
What key information is recorded on a partogram during labour?
- Cervical dilation (measured by a 4-hourly vaginal examination)
- Descent of the fetal head (in relation to the ischial spines)
- Maternal pulse (1hr), bp, temp and urine output (4hr)
- Fetal HR (every 15 mins)
- Frequency of contractions (half-hourly)
- Status of the membranes, and whether it is stained by blood or meconium
How is failure to progress in labour defined for nulliparous and multiparous women
- nulliparous - labour >20hr
- multiparous - labour >14hr
How long does the second stage of labour typically last?
approximately 1hr multiparous women and 2 hrs in nulliparous women
What interventions may be required when there are problems in the second stage of labour?
- Changing positions
- Encouragement
- Analgesia
- Oxytocin
- Episiotomy
- Instrumental delivery
- Caesarean section
How is the third stage of labour managed actively
- uterotonic drugs - IM oxytocin
- cord clamping and cutting
- controlled cord traction
Why is active management routinely offered to all women during labour?
To reduce the risk of postpartum haemorrhage
How is a delay in the third stage of labour defined?
- > 30 minutes with active management
- > 60 minutes with physiological management
How is failure to progress in labour managed
- Amniotomy - artificial rupture of membranes for women with intact membranes
- Oxytocin infusion - stimulate uterine contractions
- Instrumental delivery
- Caesarean section
What is the target contraction frequency when administering an oxytocin infusion during labour?
aim is for 4–5 contractions per 10 minutes
What are the typical positions of the fetal head during entry into the pelvis and delivery?
The fetal head normally enters the pelvis in the occipito-transverse position and delivers in the occipito-anterior position.
What should be considered if the fetal head remains in the occipito-transverse position after one hour of pushing in the second stage of labour?
Rotation with traction - ventouse
Give 4 RFs for perineal tears
- nulliparity
- large babies
- forceps delivery
- shoulder dystocia
What are the four degrees of perineal tear?
- First-degree: Superficial damage with no muscle involvement
- Second-degree: Involves the perineal muscles, but not the anal sphincter
- Third-degree: Involves the ext and int anal sphincter, but not the rectal mucosa
- Fourth-degree: injury to perineum involving the anal sphincter complex and rectal mucosa
How can third-degree perineal tears be subcategorized?
- 3A: <50% of the external anal sphincter torn
- 3B: >50% of the external anal sphincter torn
- 3C: Both external and internal anal sphincter torn
How are first and second degree perineal tears repaired
- first - usually do not require any sutures
- second - suturing on the ward by a suitably experienced midwife or clinician
How are third and fourth degree perineal tears repaired
require repair in theatre by a suitably trained clinician
What additional measures are taken to reduce the risk of complications after perineal tears?
- Broad-spectrum antibiotics to reduce the risk of infection
- Laxatives to reduce the risk of constipation and wound dehiscence
- Physiotherapy to reduce the risk and severity of incontinence
How is damage to the anal sphincter during an episiotomy avoided?
performing a mediolateral episiotomy.