Obs - Labour and Birth Flashcards
How would you take an Obstetric history?
FRAB Foetal Movements Rupture of membranes - if occurred, colour (if meconium stained e.g.) Abdominal pain Bleeding
+ SR (Headaches, nausea/vomiting, vision changes, SOB, itching etc)
Also:
- Current pregnancy - gestation, EDD, gravity and parity + any plans for delivery
- Previous pregnancies - outcomes, modes of delivery, complications and antenatal conditions, BW of babies
- Hx of diabetes, pre-eclampsia and FHx, cancers/abnormal smears
- PMH and DHx important e.g. epilepsy, DM, chronic conditions
- Gynae Hx - cancers/abnormal smears
- BLOOD GROUP (i.e. Rh status)
What is normal labour defined as and what is the epidemiology of modes of delivery? What is a common DDx?
Labour = painful uterine contractions –> cervical effacement and dilation
600,000 babies born/year
- 60% natural (inc induction)
- 30% C-section
- 10% instrumental
Braxton-Hicks = not true labour contractions, may be painless and NO cervical changes
What is cervical cerclage?
IF someone’s cervix is dilating due to cervical insufficiency then you may perform cervical cerclage (a band/stitch to keep the cervix closed until labour)
What are the 3 stages of labour?
1st stage: from the start of painful uterine contractions until the cervix is fully dilated (10cm). May take many hours (12-20h*)
> Latent 1st –> begins with painful, irregular contractions, cervix dilates from 0-3cm
> Active/Established 1st –> Regular painful contractions, 4/+cm - 10cm
2nd stage: starts with the urge to push and ends with the delivery of the foetus
> Analgesia (‘1,2,3 and analgesia = +1h)
–> In nulliparous women = 3h with epidural or 2h with no epidural
–> In multiparous women = 2h with epidural or 1h with no epidural
3rd stage: delivery of the placenta and foetal membranes, may last up to 30 mins
What is the progress of labour dependent on?
3 Ps:
Power - of contractions
Passenger - diameter of foetal head
Passage - dimensions of pelvis
What are the stages of baby delivery: [see pic for help]?
- Head floating, before engagement*
- Engagement, flexion and descent
- Further descent and internal rotation (face toward mothers spine)
- Complete rotation, beginning extension
- Complete extension - head is emerging from the vaginal canal
- Restitution (external rotation - bringing the head in line with the shoulders)
- Delivery of anterior shoulder
- Delivery of posterior shoulder
FROM TUTORIAL:
- Baby is OT (occiput-transverse) at entry to the pelvic floor
- Head is flexed to enable smallest head diameter
- Rotation to OA to enable exit from pelvic outlet and descent down
- Head extension to enable delivery
- Restitution = rotates back to OT to enable shoulder exit from the pelvic outlet and delivery
The changes in denominator position enable the baby to fit through the widest parts of the pelvis.
*engagement = when widest part of foetal head passes through the widest part of the maternal pelvis successfully
What is the Bishop’s score? What do the scores indicate?
A score used to estimate how likely one is to go into labour soon. 5 parameters:
Cervical position - 0->1->2 (posterior, intermediate, anterior, -)
Cervical consistency - 0->1->2 (firm, intermediate, soft, -)
Cervical effacement - 0->1->2->3 (0-30%, 40-50%, 60-70%, 80%)
Cervical dilation - 0->1->2->3
(<1cm, 1-2cm, 3-4cm, >5cm)
Foetal station* - 0->1->2->3
(-3, -2, -1,0 and +1,+2)
*Position of baby’s head relative to maternal ischial spines
Scores: (0-13)
<3 - IOL unlikely to be successful
5 or less - IOL with PV prostaglandin gel should start labour or ripen cervix
–> [<5 = unlikely spontaneous labour]
6-8 - ARM or artificial rupture of membranes (amniotomy +/- oxytocin infusion if labour doesn’t begin)
9/+ - labour likely to occur spontaneously
How would you manage stage 1 of labour? What is classified as ‘delay’ and what are some types/causes?
Mx:
- 1:1 midwifery care
- Vaginal examinations 4-hourly or as clinically indicated
- Labour progress is monitored using a partogram:
- –> normal progress = ~1cm/hour (a well-flexed head will speed this up)
- –> delay* = <2cm over 4h
- Adequate analgesia +/- antacids and hydration and light diet to prevent ketosis, which can impair uterine contractility
- Note: membrane may be ruptured or intact at this stage
Latent 1st phase
- > Mobilise and managed away from the labour suite (standing may encourage process of labour)
- > Avoid intervention
- Delay
- If membranes intact then initiate ARM and review in 2h
- If membranes ruptured, give oxytocin, increasing every 15-30mins until contractions are regular. Once regular, review 4-hourly
Types:
- Primary dysfunctional labour = <2cm dilation in 2h, never progressed properly, most commonly due to ineffective uterine action
- Secondary arrest of labour (progressed well, then stopped)
- Prolonged latent phase
- Cervical dystocia - rare, where cervix doesn’t dilate properly
How would you manage the 2nd stage of labour? What is classed as a delay? What is crowning?
First sign of 2nd stage is the URGE to PUSH (w 10cm dilation)
- > Full dilation confirmed by vaginal examination, if head is not visible
- > Women should be discouraged from lying supine or semi-supine
- > Use of epidural/spinal anaesthesia may interfere with the normal urge to push, therefore 2nd stage is usually diagnosed with routine scheduled vaginal examination
Passive 1st stage:
- No pushing
- Eg. if Epidural in, then 1h wait
Delay/Prolonged 2nd stage:
- > In nulliparous women normally takes 2h or 3h with epidural
- > In multiparous women, takes 1h or 2h with epidural
- Longer than 1/2h (depending on parity) = delay
- If membranes intact, initiate ARM and review in 2h
- If ruptured, give syntocinon and then review 4-hourly
- If no progress, then consider instrumental delivery
Delivery:
- > Watch the perineum - between contractions, the elastic tone of the perineal muscles will push the head back into the pelvic cavity -> when head no longer recedes between contractions = CROWNING and indicates delivery is imminent
- > As crowning occurs, hands of the midwife are used to flex the foetal head and guard the perineum
- > Once the head has crowned, the mother should be discouraged from bearing down by telling her to take rapid, shallow breaths
What is done in the immediate care of the neonate?
- Baby takes first breath within seconds
- No need for immediate clamping
- Once cord is clamped, the baby is dried and then has its APGAR score calculated at 1 and 5 mins (>7 is normal) + VitK injection given in delivery room also
- Immediate skin-skin contact helps oxytocin release and bonding
- Initiation of breast feeding should be done in 1st hour of life, followed by routine measurements (HC, weight, temperature)
What are the causes of postpartum haemorrhage?
4 Ts: Tone - uterine atony (commonest = 70%) Trauma - laceration (20%) Tissue - retained products (10%) Thrombin - coagulopathy (1%)
How is the 3rd stage of labour managed?
Mx:
- Expulsion of placenta and foetal membranes
- Normally takes 5-10 mins
- Mx can be described as active or physiological
Active Mx: [recommended to all women]
- 10 IU oxytocin IM/ ergometrine (only oxytocin if hypertensive) - given on anterior shoulder immediately after delivery and before the cord is clamped and cut
- Cord clamped after 1-5 mins
- Use controlled cord traction to remove the placenta
- -> signs of placental separation = gush of blood, cord lengthening, uterus becomes round and uterus rises
- -> Uterine inversion is a rare complication
- -> IF no bleeding occurs, attempt again after 10 mins (2% cases have failure of this method)
- Prolonged 3rd stage defined as >30 mins for active Mx and >60 mins for physiological (move to active after this)
Physiological management:
- Placenta is delivered by maternal effort with no uterotonic drugs
- Associated with more bleeding and greater need for blood transfusions
- If haemorrhage occurs or placenta undelivered after 60 mins then active Mx recommended
- If retained, examination under anaesthesia and MROP
Post-delivery
- Inspect placenta for missing cotyledons and succenturiate lobe
- Inspect vulva for tears
How is labour induced?
IOL:
1st - Membrane sweeping
- > Offered prior to formal induction
- > Repeat if labour not starting
- > Nulliparous women - offer at 40-41 weeks, Multiparous - offer at 41w
2nd - Prepare the cervix with prostaglandins (E2)
- > Preferred formal method of induction
- > Gel, tablet (1 dose followed by 2nd dose after 6h) OR pessary* (1 dose over 24h)
- > MAX 2 doses
- > Risk of uterine hyperstimulation
- > In cases of intrauterine foetal death, misoprostol and mifepristone may be used instead
3rd - ARM
- > Artificial rupture of membranes i.e. amniohook
- > NOT first line
4th - Syntocinon (synthetic oxytocin IV)
5th - CS
SUMMARY*:
Order: Propess –> Prostin if insufficient pessary, max 2x 6-hourly –> ARM –> Syntocinon –> CS
When might IOL be indicated? And when might it NOT?
IOL indications:
- > Prolonged pregnancy (from 41w) - if declined, twice weekly USS and CTG
- > Maternal request in exceptional circumstances, considered at 40w/after
- > IU foetal death - offered if membranes intact but indicated if ruptured membranes, infection or bleeding (induced with oral mifepristone and then pristine/misoprostol)
-> Previous CS - use pristine/propess but increases risk of uterine rupture and need for a second CS
NOT indicated:
- > PPROM (pre-term pre-labour rupture of membranes) - avoid induction before 34w; after 34w use prostin/propess but be aware of infection risk
- > Breech/transverse lie - not recommended (only consider if CS and ECV declined or unsuccessful)
- > severe IUGR - CS indicated
- > Suspected foetal macrosomia
What analgesia is used in labour?
Non-pharmacological:
- TENS
- Breathing techniques
- Massages
Pharmacological:
- Paracetamol, codeine
- Entonox (50% NO in O2): SE = nausea, light-headed, dry mouth
- Meperidine (pethidine, IM 1mg/kg): SE = ‘sleepy baby’, low baby RR, constipation
- Morphine (0.1-0.15mg/kg) or Diamorphine (5-7.5mg IM): SE = ‘sleepy baby’, low baby RR, constipation
- Fentanyl PCA 20microgram bolus with 5 min lockout: SE = ‘sleepy baby’, low baby RR, constipation
Surgical: [later stages]
- SE = slow labour, increased instrumental risk
- Lumbar epidural [bupivacaine, ropivacaine, levobupivacaine, chloroprocaine]
- Combined lumbar-spinal epidural [fentanyl 10-25mcg ± bupivacaine 2.5mg]
What is puerperal pyrexia? How is it caused and managed?
Puerperal pyrexia = fever >38 in first 14d following delivery
Causes = ENDOMETRITIS»_space;> UTI, VTE, mastitis, wound infection
Mx - until fever has reduced for at least 24h
-> IV Clindamycin AND IV gentamicin
How is LGA defined? What 3 tools can be used prenatally to determine this?
LGA is used to define macrocosmic babies, usually 4 or 4.5kg and above at term
-> 10% pregnancies
3 tools:
- Symphysis-Fundal height (SMH) - >90/95th centile for GA (foetal biometry)
- Abdominal circumference - >90/95th centile for GA
- Estimated foetal weight - > >90/95th centile for GA
What are some RFs for LGA?
Main RFs:
- High BMI/Obesity
- Gestational or DM
Others:
- Multiparity
- Polyhydramnios
- Advanced maternal age
- Molar pregnancy
- Syndromes e.g. Soto’s, Beckwith-Wiedmann
How would a baby LGA present? What Ix would you consider?
On inspection - excessive distension for GA
Abdomen - increased SFH, increased abdominal circumference
Ix:
- OGTT for gestational diabetes
- Bloods -> serum BHCG
- USS - liquor volume, biometry
- Genetic testing
How would you manage a baby LGA? (hint: depends on when detected)
Detected at 18-21w
- Repeat scan
Detected at 24-36w
- If acceleration of growth, arrange a USS for foetal biometry
- If no drop/rise growth then reassure this is normal and arrange another routine scan
- Offer OGTT for GD
Detected at 36-40w
- If SFH is >90th centile on routine measurements, arrange for USS for foetal biometry
- If EFW and AC on USS are >95th centile, then return to routine care
- Perform OGTT for GD
- Care in labour + postnatally as per GD Dx at earlier gestation
Note: need to plan delivery and discuss risks (shoulder dystocia, nerve injuries, prolonged labour) –> Offer CS
What are some complications of LGA babies?
- Shoulder dystocia
- Hypoglycaemia in GDM
- Respiratory distress syndrome (due to GDM + need of earlier delivery)
- Intrauterine deformations (metatarsus adductus, hip subluxation)
- Perineal tear
- Increased mortality
But prognosis is good/indifferent to normal babies if detected and managed earlier
How is a baby SGA defined? What is the difference between IUGR and SGA? What are some RFs for SGA?
SGA - derived from birth weight –> describes a baby with AC or EFW in the 10th or lower centile for GA
-> 5% pregnancies
IUGR - derived from growth rate –> a baby with a reduced growth rate and so becomes SGA
RFs: Major: [Maternal] -> Previous still birth -> Antiphospholipid syndrome -> Renal disease -> Maternal age >40 -> Smoker >11 cigs/day Major: [Foetal/other] -> Chromosomal abnormalities (symmetrical IUGR) -> Infection (CMV, rubella) -> Multiple pregnancy -> Placental insufficiency (asymmetrical IUGR - normal head, but AC and peripheries smaller)
Minor: [See RCOG for full list]
- Maternal age >35
- Nulliparity
- BMI <20 or 25-34.9
- Smoker 1-10 cigs/day
- IVF singleton pregnancy
How would you Ix a baby SGA?
Ix:
- > Assess RFs at booking visit (1st trimester)
- If 1/+ major RF or 3/+ minor RFs then reassess at 20w
- At 20w and still at risk, consider:
- > Minor risk (3/+ minor RFs) = uterine artery doppler (20-24w) and if abnormal –> serial USS from 26-28w
- > Major risk (1/+ major RFs) = foetal size and umbilical artery doppler (serial USS from 26-28w)
- > Screen for congenital infections
IF SGA or IUGR:
-> USS biometry (biparietal diameter, HC, AC and femur length) and UMBILICAL ARTERY doppler serial measurements should be taken (every TWO weeks)
How would you manage SGA baby?
Mx:
- Stop smoking, drugs and alcohol
- [Low dose aspirin may be used in preventing IUGR in high-risk pregnancies, NOT reversing however]
Monitoring:
- SFH or risk status determined at booking or antenatal appointment
- Confirm SGA with foetal biometry (20w)
- Uterine artery doppler (20-24w)
- -> Normal = repeat scans every 2w from 20-24w
- -> Abnormal = serial growth scans every week from 26-28w and doppler USS can be performed 2x/week (umbilical artery flow)
Delivery:
- IMMEDIATE delivery indications = abnormal CTG (+reduced foetal movements) and reversal of end-diastolic flow of umbilical artery (placental insufficiency)
- Delivery by 37w is usually necessary depending on severity and gestation
- –> steroids given <36w
- –> Consultant led clinics and decision making
What are some complications of SGA babies? What is their prognosis?
Complications:
- Stillbirth
- Post-natal hypoglycaemia
- Birth asphyxia
- Intrapartum foetal distress
- Pre-term labour
- Neurodevelopmental delay
Prognosis - increased perinatal morbidity, increased neurodevelopmental delay if onset <26w
What is the difference between PROM and PPROM?
PROM = Pre-labour rupture of membranes
- Spontaneous rupture of membranes before labour at TERM (37w/+)
- Occurs in <10% women
- Natural physiological cause e.g. Braxton-Hicks contractions and cervical ripening –> weakened membranes
PPROM = pre-term pre-labour rupture of membranes
- Spontaneous rupture of membranes before onset of labour in pregnancy from 24+0w to 36+6w
- Occurs in 2% pregnancies
- Can be caused by weakened membranes from infective cause
How may PROM/PPROM present? How would you Ix this?
Sx:
- PROM vs PPROM depends on whether pregnancy is at term
- Sudden gush of fluid PV -> constant trickle
- Contractions - if regular and painful then PTL, if not BH
- General examination - assess for signs of infection such as tachycardia or fever
Ix:
1st = Speculum
-> Amniotic fluid pooling is diagnostic of P/PROM - also the Os may be open or closed
-> If no pooling, test IGFBP-1 or PAMG-1
-> Do NOT use KY jelly as will complicate FFN result
-> Only perform if ROM isn’t evident
-> DO NOT do bimanual as increases infection risk
If >30w, contractions present and Os closed then do
= TVUSS for cervical length
- <15mm is likely to be PTL
- >15mm is unlikely to be PTL
Do not perform diagnostic tests for PPROM if labour becomes established - i.e. bulging membranes, abdominal pain, in a women presenting suggestive of PPROM -> ADMIT to labour ward
2nd = IGFBP-1 (insulin growth factor binding protein 1) or PAMG-1 (AKA Partosure = placental alpha-microglobulin 1)
3rd = FFN + (foetal fibronectin) from gestational sac MAY be detectable
- <24w and >34w would be detectable, and + in PPROM but not detectable in 24-34w
Mx: as per rupture of membranes i.e. not ruptured = PTL and ruptured = PROM/PPROM
How is PROM and PPROM managed? What are RFs for each? What are complications of each?
RFs = APH, previous PROM/PTL, smoking, trauma, UTI, multiple pregnancy, uterine abnormalities, cervical incompetence
PPROM
Mx:
- ADMIT and expectant management until 37w if no complications
- Erythromycin for 10d/until labour established
- CS if <34w
- MgSO4 if <30w OR in labour OR planned birth in <24h
- Regular assessment with clinical assessment, bloods and CTG
Risks = maternal sepsis, cord abruption, foetal death, prematurity, cord prolapse
PROM:
- if <24h then expectant management, most women go into labour within 24h
- >24h then IOL - 4-hourly temperature and 24h foetal monitoring; augment with prostaglandin or oxytocin infusion
OR
- Meconium seen - induce labour ASAP
PACES advice:
- 60% women go into labour within 24h, but will attempt to induce after 24h
- Risk of neonatal infection if slightly raised (1% vs 0.5% for intact membranes)
What is the definition of PTL, very PTL and extremely PTL? What are the causes of PTL?
Pre-term labour is when labour occurs at 32-37w GA
Very PTL = labour 28-32w GA
Extremely PTL = labour at <28w
-> 24w is seen as the limit of viability (55% survival)
Causes of PTL:
- Infection (20-40%)
- Uterine abnormalities
- Cervical procedures
- Overdistension of the uterus i.e. multiple pregnancy, polyhydramnios
What are RFs for PTL?
RFs:
- Previous PTL/PROM/PPROM
- Miscarriage at 16-24w
- Cervical biopsy
- INFECTION
- Structural - uterine abnormalities, pre-eclampsia
- Mechanical - stretch
- Smoking, high BMI, drugs, extreme ages
How would you Ix and Mx PTL? What are complications of PTL?
Ix:
- > Abdo exam
- > Speculum
- > TVUSS if Os closed
- > CTG monitor
- > Urine dip +/- MC&S if indicated
Mx:
[Note: Ruptured membranes = PPROM guidance]
Non-ruptured membranes:
-> Tocolysis if 34w (1st=Nifedipine, 2nd=Atosiban)
-> Corticosteriods if 34w for 24h (+insulin in diabetics)
-> MgSO4 for 30w; labour OR planned birth <24h
-> Surgical = emergency ‘rescue’ cerclage indicated if 16-28w, dilated cervix and exposed UNRUPTURED membranes however is contraindicated in infection, bleeding and uterine contractions
-> Prophylactic vaginal progesterone (16-24w) / cervical cerclage offered to women:
History of PTL (<34w GA) AND cervical length <25mm
History of >16w GA miscarriage AND cervical length <25mm
Cervical length <25mm AND history of PPROM
Cervical length <25mm AND cervical trauma
Complications:
- Preterm birth complications = ‘big 4’:
- -> RDS (of which O2 treatment can also cause ROP)
- -> NEC
- -> IVH
- -> Periventricular leukomalacia (PVL)
- Sepsis
What is a hydatiform mole? What is it caused by and what are RFs associated with it?
A benign tumour of the trophoblastic tissue due to abnormal fertilisation leading to formation of a ‘mole’:
- Complete mole = empty ovum fertilised by either 2 sperm, or 1 sperm which duplicates its DNA (46XY or 46XX)
- Partial mole = normal ovum (1 set maternal chromosomes) fertilised by 2 sperm, or 1 sperm which duplicates its DNA (69XXY or 69 XXX)
RFs:
- Extremes of reproductive age
- Previous GTD
- Diet - low beta carotene, low saturated fat
- Ethnicity - Japanese, asians, native Americans
How may a pregnant lady present with a molar pregnancy?
Sx:
- Large for GA (e.g. SFH)
- Painless PV bleeding (i.e. miscarriage)
- Hyperemesis from elevated bHCG
- Symptoms of hyperthyroidism (rare, due to bHCG mimicking TSH)
- [Often seen on USS before symptoms]
How would you Ix a suspected molar pregnancy?
Ix:
- Bloods - grossly elevated bHCG, low TSH and high T4 due to mimicking by bHCG
- Pelvic USS
- -> Complete mole = ‘snowstorm’ appearance, ‘cluster of grapes’, no foetal parrts
- -> Partial mole = foetal parts seen, NO snowstorm or ‘cluster of grapes’
How would you manage a molar pregnancy?
Mx:
- Urgent referral to a specialist centre for GTD
- Surgical management using ERPC (evacuation of retained products of conception)
- Monitoring - serial bHCG monitoring in specialist centre, given methotrexate if rising/stagnant levels and avoid pregnancy until 6m of normal levels
- Advice
- -> NO conceiving until f/u complete (use barrier and COCP)
- -> Avoid IUDs until HCG normalised
- -> If continues to rise, query choriocarcinoma?
What are complications of a molar pregnancy? What is the risk of recurrence?
- Can progress to malignancy (20% complex moles, 2% partial moles)
- Partial mole has 0% risk to choriocarcinoma
- Complete mole has 10% risk of invasive mole and 2.5% risk choriocarcinoma
- Recurrence risk 1%, if 2/+ molar pregnancies then rises to 17%
