Normal labour Flashcards
Definition/Diagnostic criteria of true labour
- Regular, painful uterine contractions
- Increasing frequency and intensity
- Cervical effacement (shortening of cervix until indistinguishable from uterine wall)
- Progressive cervical dilatation (≥3cm is active)
- Descent of fetal presenting part in the pelvis
False labour
aka Braxton-Hicks’ contractions
- Irregular uterine contractions that are not of increasing frequency or intensity
- Last 4-8 weeks of pregnancy
- Normally painless, unpredictable and spontaneous
- Not a/w progressive cervical dilation or effacement
2nd stage of labour
From full dilatation to delivery of fetus
- primigravida: ~2h
- multigravida: ~1h
+ 1 hour if epidural given (no pressure from descending fetus -> passive descent of fetus, allow mom to regain sensation to push)
1st stage of labour
From onset of painful REGULAR uterine contractions to full dilatation of cervix (10cm)
- Divided into 2 phases: Latent vs Active
- Monitor descent of fetal head
3rd stage of labour
From delivery of the fetus to delivery of placenta
- Up to 30 mins in both nulli and multiparous women
Changes to mommy preceding labour
- False labour pains (braxton hicks)
- Lightening
- Fundal height drops a bit as baby drops into pelvis -> feels a bit easier to breathe - Discharge of mucus plug
- Cervical changes (effacement and dilatation)
- Show
- Can be blood-stained mucoid plug
What is ‘the show’ in labour?
Loosening and expulsion of the mucus plug that has been blocking the cervical canal during pregnancy
Duration of 1st stage of labour
Primigravida: 12h
Multigravida: 6h
1st stage of labour: Latent phase (variable)
- Effacement of cervix
- Dilatation of cervix from 0-3cm
1st stage of labour: Active phase (2-9h)
Rapid dilatation of cervix from 3-10cm with regular uterine contractions
-> Nulliparous women: 1cm/h
-> Multiparous women: 2cm/h
- Entire cervical length is retracted into LUS
- Ensure delivery 12h from now
*if uterus keeps contracting too much, this can cause uterine atony -> PPH -> rupture
If progress of cervical dilatation is <1cm/h for normal primiparous women, consider:
Uterine dysfunction
Fetal malposition
Cephalopelvic disproportion
Monitoring descent of fetal head
- Crichton’s method: Abdominal palpation - in “fifths”
- Vaginal examination: “Station” relates the level of the lowest point of fetal head with ischial spine
*Eg. 1cm above/below ischial spine is +1/-1 etc
What is LIE?
Relationship of longitudinal axis of the fetus to
the longitudinal axis of the mother
- longitudinal vs transverse vs oblique
What is PRESENTATION?
Part of the fetus directly overlying the pelvis
- cephalic vs breech vs shoulder
- cannot tell on abdo palpation
What is PRESENTING PART?
Part of the fetus that is
felt through the cervix on vaginal examination
- If baby is fully flexed, means baby is in cephalic presentation: first contact point is vertex
- If baby is fully extended, means baby is not in cephalic presentation: first contact point is face