Module 5A: Normal Labour and Birth Flashcards
What does “bloody show” mean?
- vaginal discharge that originate in the cervix
- consist of blood and mucous
What is the positive sign labour has commenced (2)?
- regular contractions that are accompanied by cervical changes
- changes include the cervix moving from a posterior to anterior position, shortening and thinning (effacing), and dilating
- contractions become progressively stronger (intensity), more frequent (frequency), and last longer (duration)
What are some hormonal physiology of labour and birth that involves maternal preparation? oxytocin? estrogen?
- Rising estrogen levels: activating the uterus for labour
- increases in oxytocin and prostaglandin activity: cervical ripening
- Increasing inflammation: activate the cervix and uterus
- Elevations in mammary and central oxytocin and prolactin receptors: promote breastfeeding and maternal infant attachment
What are some hormonal physiology of labour and birth that involves fetal preparation?
- Pre-labour maturing of lungs and other organ systems
- Pre-labour increase in epinephrine-norepinephrine receptors, giving protection from labour hypoxia
- in- labour, preservation of blood supply to heart and brain, via the catecholamine surge, with neuroprotective effects
What is oxytocin? 4 Roles?
- hormone
- secreted by posterior pituitary gland
Plays a role in :
- preparing the body for labour and
- optimizing labour by causing rhythmic contractions,
- promoting calm,
- reducing fear and stress
- promoting maternal-infant attachment
After birth, what roles (2) does oxytocin play for mother?
- promoting uterine contractions after birth which helps postpartum bleeding
- aid in uterine involution
What is the role of beta-endorphines in labour?
- secreted by posterior pituitary gland
- by providing analgesic and adaptive responses to stress and pain
What are the 5 hormones of labour?
- beta-endorphines
- catecholammines
- cortisol
- estrogen
- oxytocin
What is the role of Catecholamines (epinephrine, norepinephrine, and dopamine)?
- Elevations in epinephrine/norepinephrine in late labour also support newborn transition to extrauterine life
- Catecholamines are the primary mediators that prepare the fetus for birth and support the multi-organ transition to extrauterine life
What are 4 roles of cortisol (stress hormone) during labour?
- elevated during labour
- may promote contractions
- increase central oxytocin effects on maternal adaptations and attachment
- enhance postpartum mood
- prepares fetus for birth
- promote lung maturation and clearance of fetal lung fluid
What are 4 signs of true labour?
- vaginal exam to assess whether cervix is effaced and dilated
- Contractions occur regularly, become stronger, longer, and more frequent
- Contractions become more intense with walking
- Contractions usually felt in lower back, radiating to lower abdomen.
- Contractions continue despite use of comfort measures and rest
- Cervix softens, moves from posterior to anterior position, thins (effaces) and dilates
- Presenting part of fetus usually engaged in pelvis now
- May or may not see bloody show
What are 4 signs of false labour?
- Contractions occur irregularly or stop and start
- Contractions may stop with activity such as walking or stop with rest
- Contractions can be felt in low back or abdomen above the umbilicus.
- Contractions slow or stop with comfort measures
- Cervix does not change, may still be posterior
- Fetus may not yet be engaged in pelvis
What are the 5 P’s of labour?
- passager
- passageway
- powers
- position
- psychological factors (psyche)
What is the passenger of the 5 P’s?
- passenger relates to the fetus
- the way the fetus moves through the birth canal determined by: size of fetal head, fetal presentation, fetal lie, fetal attitude, fetal position
- placenta could also be considered a passenger since it must be expelled through the birth canal after the birth of the baby
What is the fetal presentation? What are the 3 presentation?
- the part of the fetus that enters the pelvic inlet first and leads through the birth canal
- cephalic: head first
- breech: buttocks, feet or both first
- shoulder
What is the fetal lie? What are the 3 fetal lie?
- the relationship between the long axis (spine) of fetus and the long axis (spine) of women
Lies:
- longitudinal or vertical: long axis of fetus is parallel to the long axis of mother
- transverse, horizontal
- oblique or diagonal: long axis of fetus is at a right angle diagonal to the long axis of mother
What is the fetal attitude?
- the relation of the fetal body parts to one another
- normal attitude is general flexion
- chin flexed onto chest and thighs/legs flexed, arms crossed over body
What is the fetal position?
- the relationship of the reference point of presenting part (occiput, sacrum, mentum [chin], or sinciput) to the 4 quadrants of maternal pelvis
- denoted by three-part abbreviation
- (R) right or (L) left
- (O) occiput or (S) scarum, (M) mentum or Sc for scapula [shoulder]
- (A) anterior, (P) posterior, (T) transverse
- left occiput anterior (LOA): means occiput is the presenting part in the left anterior quadrant of maternal pelvis
- the presentation or presenting part indicates that portion of the fetus overlies the pelvic inlet
What is the fetal station?
- relationship of presenting part to an imaginary line drawn between the maternal ischial spines
- is a measure degree of descent of presenting part of fetus through birth canal
- when the lowermost portion of the presenting part is 1cm above the spine, it is noted as being minus (-) 1
- at the level of spine, station is referred as zero (0)
- birth is imminent when presenting part is at +4 or +5
= -5 floating body
= 0 is engaged in pelvis
= +2 for spontaneous pushing
= +5 crowning
What is engagement in terms of fetal position?
- the term used to indicate the largest transverse diameter of presenting part has passed through maternal pelvic brim or inlet into the true pelvis
- usually corresponds to station 0
What is the passageway of the 5Ps? Composed of (5)?
- the passageway or birth canal composed of mothers:
- rigid bony pelvis,
- soft tissues of cervix,
- pelvic floor muscles
- vagina, and
- introitus (external opening of vagina)
What is the powers of the 5Ps?
- relates to the uterine contractions that are needed to dilate the cervix and push the fetus down and out the passage
- labour contractions are involuntary but included in the powers are voluntary bearing down efforts of the women during second stage and birth
- primary powers: involuntary uterine contractions (signal the beginning of labour)
= once cervix is dilated, voluntary bearing-down efforts by woman –> secondary powers - secondary powers: Maternal pushing efforts during uterine contractions
What are 3 terms to described primary powers (involuntary contractions)?
- frequency: the time from the beginning of one contraction to the beginning of the next
- duration: the length of contraction
- intensity: strength of contraction at its peak
- primary powers are responsible for the effacement and dilation of cervix and descent of fetus
What is the position of the 5 P’s?
- refers to the woman’s position as she labours
- certain positions facilitate and enhance the labour process
What are 4 Psychological factors (psyche) of the 5 P’s include?
- individual woman’s strength,
- past Hx,
- ability to cope with labour pain,
- perception of pain,
- level of fear/anxiety,
- her values/beliefs,
- intentions as they related to labour and birth
What are the 6 bones of the fetal skull?
- frontal bone: forehead region
- two parietal: bilateral skull bones form the lateral walls of cranium
- two temporal: the sides and base of brain
- occipital bone: covers the back of the head
What are the names of the fontanelles and how can you tell the difference between them?
- anterior and posterior
- anterior: diamond shaped
- posterior: tranigular shaped
What happens to the fetal skull as it moves through the maternal pelvis?
- bones of fetal skull not attached: ability to move during the birthing and can overlap slightly (molding)
- other feature that enables the fetal skull to accommodate its way through the birth canal is that it normally flexes to present its narrowest diameter
What are the three planes/parts of the true pelvis that play a role in labour?
- inlet or brim: upper border of true pelvis
- midpelvis or cavity: curved passage
- outlet: lower border of true pelvis
What does the soft tissue of passageway includes (5)?
Soft tissues in the pelvis (passageway) include:
- the lower uterine segment,
- the pelvic floor muscles,
- the cervix,
- the vagina, and
- the introitus
What are considered the primary powers?
- involuntary uterine contractions
- primary powers are responsible for effacement and dialtion of cervix and descent of fetus
What are considered the secondary powers?
- maternal pushing efforts during uterine contractions
- as soon as presenting part reach pelvic floor, contractions change in character and become expulsive
- labouring woman experience an involuntary urge to push
- she uses secondary powers (bearing down efforts) to aid in expulsion of fetus as she contracts her diaphragm and abdominal muscles and pushes
- secondary powers have no effect on cervical dilation but importance in the expulsion of infant from uterus and cercix is fully dilated
What are 4 advantages of changing women’s position during labour?
Frequent changes of position during labour
- relieve fatigue,
- increase comfort, and
- improve circulation.
- Certain positions are anatomically beneficial in allowing gravity to advance the fetus through the birth canal and may help in opening the pelvic diameters to allow fetal descent and rotation.
What are 4 gravity enhancing positions that can be used during labour?
- walking
- standing
- sitting
- squatting
What is the cardinal movements?
- in normal labour and birth: the passenger moves through the passage with a series of maneuvers, called the cardinal movements
- cardinal movements are part of the mechanism of labour
- are a combination of movements with some occurring simultaneously
- the power of uterine contractions accompanied by maternal positioning aid the fetus in its descent and rotation through the pelvis.
- For most labours it is the fetal head that leads the way as the fetus maneuvers through the maternal pelvis
What are the two interventions that promote, protect and support normal birth?
- upright postures
- freedom of movement
What are the 7 cardinal movements?
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- Restitution and external rotation
- Expulsion - The birth of the entire body marks the time of birth for the baby
What are the 3 phase of the first stage of labour?
- the latent phase: starts when contractions are regular, painful and cervical effacement and dilate commences (from 0 to 3 cm dialated)
- the active phase: refers to the time when labour is well established becoming more painful and usually more frequent and longer (cervix thins and dilates from 4 cm to 7 cm)
- the transition or accelerated phase: usually occur when cervix is 8-10cm (women feels she wants to bear down)
What is effacement and dilation?
- effacement: shortening and thinning of cervix during first stage of labour (ex. 50% effaced)
- dilation: the enlargement of widening of cervical opening that occurs during labour (ex. diameter is from closed to 10cm dilated)
The first stage of labour is commenced by what? Ends when?
- commences with the onset of regular contractions accompanied by cervical changes
- ends when the cervix is fully dilated
What are 3 steps that happens during the first stage of labour?
- the presenting part of the fetus (most often the occiput) descends and rotates through the birth canal.
- flexed fetal head: flexion allows a narrower diameter of the head to move through the pelvis
- by the time full dilatation of the cervix is accomplished the presenting part is usually at the outlet of the bony pelvis, starting to make its way under the pubic arch
How are the uterine contractions at each phase of the first stage of labour?
- Uterine contractions increase: (time for nullip woman)
- latent phase: every 5-30 minutes (last approximately 6-8 hours)
- active phase: every 3-5 minutes (averages between 3-6 hours)
- transition phase: every 2-3 minutes (may last 1-2 hours)
- Times are generally shorter for a multiparous woman