10. Labour And Delivery Flashcards
What s the first stage of labour?
Onset of regular contractions until the cervix is fully dilated (latent and active)
Regular painful contractions, at least 2 per 10 mins
What is 2nd stage of labour?
Begins when the cervix is fully dilated to the birth of the baby
What is the 3rd stage of labour?
From birth of baby to delivery of placenta and membranes and bleeding is controlled
What is the latent phase of labour?
Period of time, not necessary continuous, when there are painful contractions and cervical effacement and dilation up to 4 CNS
What is established/active labour?
When there are regular painful contractions and progressive dilatation from 4cm
What is the transition phase of labour?
From 8cm dilated to 10cm
What happens in pre-labour?
Lightening occurs 2-3 weeks before labour Expansion of lower segment Fetal head emerges Symphysis pubis widens, sacro-iliac joints relax Pelvic floor replaces Increased vaginal secretions Frequency of micturition Braxton Hicks contractions Taking up of cervix
How does the cervix change in pregnancy?
From 24 weeks, cervical cells gradually change in collagen content - take up more water
Allows it to change shape more easily
Describe the up regulation of oxytocin in pregnancy/birth
Makes myometrium more sensitive
Ferguson’s reflex: contractions -> fetal head presses on cervix -> release of oxytocin from posterior pituitary gland -> contractions
Positive feedback loop
What are the hormones involved in labour?
Progesterone Oestrogen Prostaglandins Oxytocin Endorphins Adrenaline/noradrenaline
What are the average durations of labour?
Primiparous women - 8-18 hrs
Multiparous women - 5-12 hrs
What happens in the perineal phase?
Descending fetal head displaces soft tissue
Anteriorly, bladder is pushed up into abdominal cavity to prevent damage
Stretching and thinning of urethra
Posteriorly, rectum becomes flattened into sacral curve and pressure of advancing head expels any residual faecal matter
Deep muscles of perineum dilate and displace laterally
Perineal body flattens, stretches and thins out
What are the signs of the second stage of labour?
Urge to push Expulsive uterine contractions Dilated anus Anal cleft line Rhomboid of Michaelas Blood stained show Visible presenting part Definitive diagnosis is by vaginal examination
What are the general mechanisms of birth?
Decent Flexion Internal rotation of head Extension of head Restitution Internal rotation of shoulders and external rotation of head Lateral flexion
What are the signs of separation of placenta from uterine wall?
Cord lengthening Rising/tightening of uterus Possible separation vaginal bleed Maternal pressure Valval bulge
