Pregnancy Flashcards
Naegele’s rule for EDD
first day of LMP + 7 days + 1 year - 3 months
Common medications that are teratogenic
ACEi/ARB warfarin anti-epileptics carbimazole methotrexate isotretinoin lithium
Components to assess during palpation of abdomen /uterus
SFH uterine tone and tenderness lie presentation position engagement liquor volume
Causes of bHCG levels being higher/lower than expected
higher: multiple gestation, molar pregnancy, trisomy 21
lower: ectopic, miscarriage
both: wrong dates
Major complications of pregnancy
Pre term labour IUGR GDM Miscarriage or stillbirth Antepartum or PPH Pre eclampsia
“PIGMAP”
Pre-conception care
Hx: HPC, Obs and gyn hx, PMHx, teratogenic medications, Social (SNAP, home), FHx
Exam: vitals, anthropometry, systems review, breast and cervical screening
Ix: bloods (FBC, blood typing, BBV infections, vaccine serology), urine dipstick, HPV swab
Lifestyle: SNAP and weight loss
Avoid TORCH organisms: avoid raw meats/seafood, cold cheese, cat litter, wash hands, etc
Supplements: folate and iodine
Vaccines: Influenza, dTPa, MMRV
Risk factors for foetal abnormality
- foetal/pregnancy and maternal factors
Maternal:
- previous hx of foetal abnormality
- increasing age
- teratogens
- maternal disease
Foetal/pregnancy:
- IUGR
- abnormal amniotic fluid
- persistent breech or abnormal lie
- abnormal foetal movements
Routine antenatal screening tests for foetal abnormalities
what is considered high risk
CFTS: 11-14 weeks, bHCG, PAPP-A + USS nuchal translucency
2nd trimester screen: 14-18 weeks, bHCG + AFP + UE-3 + inhibin-A
> 1/300 combined risk = high risk = offered diagnostic testing
What is cfDNA / NIPT? aka harmony test
cell free DNA / non invasive prenatal testing
alternative to CFTS to detect aneuploidy ie chromosome abnormalities in 21, 18, 13
measures cell free DNA from placenta in maternal plasma
more specific and sensitive but still requires diagnostic testing
$400 self funded
Diagnostic antenatal tests
chorionic villus sampling (CVS)
- 11-14 weeks, placental biopsy
amniocentesis
- >15 weeks
risks: spontaneous foetal loss
What does carrier screening test for and when is it done?
CF
spinal muscular atrophy
fragile X
before conception or 1st trimester
Definition of antepartum haemorrhage
> 20 weeks gestation but before birth
Examination of APH
general - LOC, pallor, pain, estimate blood loss by inspecting groin area
Vitals - haemodynamically stable
abdominal - inspect, SFH, palpate foetal lie, uterine tone and tenderness, CTG
pelvic - inspect only! do NOT do bimanual, obstetrician may do speculum
Ix and Mx for APH
mother - FBC, coagulation, G&H, cross match
Foetus - transabdominal USS, CTG
medical - TXA, betamethasone IM, anti-D if Rh-
Types of placenta praaevia
1 - <2cm from cervical os but clear of os
2 - margin of os
3 - overlying os, part of placenta in upper uterus
4 - covering os, entirely in lower segment
RF for placenta praaevia
hx of placenta praaevia past c section multiparous fibroids multiple pregnancy
what is low lying placenta and what is the management
low lying placenta = <2cm from os and <26/40
high grade or accreta - F/U 32/40
low grade - F/U 36/40
safety net
accreta - MRI
symptoms and exam features of placenta praaevia bleeding
symptoms - painless antenatal vaginal haemorrhage, sudden onset, recurrent bleeding
exam - soft abdomen with normal uterine tone, foetal parts easy to palpate, malpresentation of foetus (transverse or oblique, displaced presenting part to high and central)
Management of placenta praaevia during third trimester ie counselling, plan, mx
counselling
- low lying, blocking passage of baby
- 2 concerns - massive bleeding, baby cannot get out
- close monitoring required
- C section at 37/40
- +/- blood transfusion
- +/- hysterectomy
admit for monitoring until 37/40
Rx - betamethasone IM if <34/40, replace iron and blood as required
What is placenta accreta and what is the management
placenta implantation over previous c section scar
management similar to placenta praaevia but with higher risk of bleeding
more likely to require hysterectomy due to inability to separate placenta
RF for placental abruption
past abruption trauma poor placentation - smoking, drugs, HTN, IUGR chorioamnionitis sudden reduction in AF - PPROM, IOL
Clinical features of placental abruption
symptoms - severe constant abdo pain with woody hard uterus, +/- haemorrhage
exam - uterine tenderness, increased tone and rigidity, baby hard to palpate, longitudinal lie
What is ‘bloody show’
passage of cervical plug
small amount of blood and mucus near end of pregnancy and often before labour
5 types of hypertensive obstetric disorders
chronic HTN gestational HTN pre eclampsia eclampsia chronic HTN with superimposed pre eclampsia
gestational HTN
- definition
- risk factors
- management (conservative vs medical)
> /=140/90 on 2 separate occasions, arising >20 weeks gestation, NO proteinuria, NO end organ damage
RF: extremes of age, personal or family history, nulliparity, 1st pregnancy with new partner, obesity, DM, CKD, vascular disease
management
- <160/110 conservative (rest, SNAP)
- > 160/110 methyldopa, labetolol, nifedipine
pre eclampsia definition and evidence of end organ damage
> /=140/90 and >20 weeks gestation plus evidence of end organ damage
renal - proteinuria (2+ dipstick, >30mg/mmol PCR, >300mg/day 24hr urine), AKI (Cr >90), oliguria (<0.5mg/kg/hr)
liver - increase ALT and AST, epigastric or RUQ pain
neuro - headache, blurred vision, central scotoma, hyper reflex, clonus
haem - thrombocytopenia, haemolysis, DIC
foetus - growth restriction, distress
risk factors for pre eclampsia
maternal - extremes of age, DM, obesity, CKD, vascular disease, HTN, thrombophilia, family or personal hx of pre eclampsia, primigravida or 1st pregnancy with new partner
pregnancy related - multiple pregnancy, molar pregnancy
pre eclampsia pathophysiology
- trophoblasts have incomplete invasion into endometrium with poor development of spiral arteries (shallow placentation)
- reduced placental perfusion
- placenta releases vasoactive and prothrombotic substances
- systemic vascular dysfunction, capillary leakage and vasospasm
complications of pre eclampsia
maternal - eclampsia, renal and liver failure, HELLP, DIC, ICH, LVF, APO
foetal - IUGR, hypoxia, placental abruption, death
pre eclampsia physical examination
general - SOB, LOC, oedema, bruising, n&v
vitals
anthropometry
neuro - eye exam, fundoscopy, hyperreflexia, clonus
cardiorespiratory - S3/S4 (heart failure), APO
peripheries - oedema
abdo - liver tenderness, SFH, lie, position, presentation, engagement
USS of uterus
investigations for pre eclampsia
bedside - urine dipstick, BP
labs - urine PCR, FBC, UEC, LFT, uric acid, (+/- blood film, coagulation, fibrinogen, LDH)
foetus - CTG, USS
management of pre eclampsia
resus - call obstetrics, A&B, left lateral position, >160/110 use labetolol / methyldopa / nifedipine, caution IVF (APO), MgSO4 if seizures or neuro symptoms, midazolam if ongoing seizures
admission - immediate with monitoring and consider TOP or delivery
give corticosteroids for baby
indications to delivery in pre eclampsia
37 weeks mild PET 34 weeks severe PET uncontrolled HTN or heart failure persistent neuro signs seizures deteriorating renal function HELLP deranged LFTs severe thrombocytopenia
severe IUGR
foetal distress
placental abruption
types of mono and dizygotic twins and when they split
dizygotic - always dichorionic diamniotic (DCDA), 2 sperm and 2 ova
monozygotic - MCMA or MCDA or DCDA
DCDA - split before implantation, 1-3 days
MCDA - split as implanting, 4-7 days
MCMA - split after implantation >7 days
complications of twin pregnancies
general - usual complications of pregnancy but more severe and earlier
eg pre-eclampsia, IUGR, GDM, miscarriage or stillbirth, APH, PPH, PTL, PPROM
specific twin-twin transfusion syndrome malpresentation asphyxiation of twin 2 cord entanglement PPH
management of multiple pregnancy antenatally
- counsel
- supplements
- USS
- screening
counsel - increased risk of complications, c section delivery recommended
antenatal care - high risk clinic at hospital, USS every 4 weeks from 24 weeks
prenatal screening - bHCG, PAPP-A and NIPT less accurate
supplements - folate 5mg (not 0.5mg as usual), iodine, +/- B12/folate, +/- iron
management of vaginal delivery for twins
only done if first twin is cephalic presentation
IV access
epidural recommended
monitoring: CTG, vitals, scalp electrode, USS
delivery:
deliver 1st
immediate IV oxytocin after first delivery
leave membranes intact for second until head descended in pelvis OR ruled out cord prolapse
if CTG abnormal - forceps delivery
post dates pregnancy - definition and complications
> 42 weeks gestation
post maturity syndrome still birth macrosomia oligohydramnios foetal asphyxia from cord compressions foetal distress meconium aspiration
management of post dates pregnancy (41 week antenatal appointment)
41 week antenatal appointment
assess pregnancy - hx, foetal movements, passage of blood/fluid, vitals, abdo palp
CTG and USS
book IOL for 41+3
if declined IOL - frequent CTG and AFI monitoring until delivery
SGA and IUGR definition and parameters used to assess size
<10th percentile
SGA - may or may not be pathological
IUGR - pathological cause
head circumference
abdominal circumference
foetal length
1st trimester; CRL
3rd trimester; biparietal diameter, HC, abdominal circumference
Risk factors for IUGR
maternal: small parents, Asian, extremes of age (<18, >35), previous SGA baby, malnutrition, smoking, substance abuse, HTN, PET, anaemia, chronic disease
foetal: chromosomal abnormalities, multiple pregnancy, intrauterine infection, congenital anomalies
placenta: smoking, twin to twin transfusion syndrome, abruption, accreta, infarction, low placental weight or SA
Symmetrical vs asymmetrical growth plot
symmetrical: growth trajectory remains constant at the lower end of normal
asymmetrical: growth trajectory crosses lines
Complications of IUGR/SGA
intrauterine - stillbirth
labour - asphyxia (insufficient utero-placental perfusion in labour)
postnatal - low BGL, polycythemia, respiratory distress
antenatal management of IUGR
- maternal
- Ix
- Rx
- delivery
maternal - assess for pre eclampsia, screen for infection
ix
- offer amniocentesis
- USS and foetal doppler
- CTG
Rx
- refer maternal foetal medicine
- low dose aspirin
- prednisone if <34 weeks
delivery
- depends on results
- early delivery if poor placental flow, growth stops, abnormal AFI
LGA causes and complications
causes: large mum, African, GDM, obesity, congenital anomalies
complications: shoulder dystocia, fractures, neonatal resp distress, MAS
Causes and risk factors for sepsis in pregnancy/labour/postnatal
causes: episiotomy, CS, PROM, septic abortion, chorioamnionitis, urosepsis, aspiration pneumonia
RF
- multiple VE during labour (>5)
- CS
- PROM
- obstetric manoeuvres
- multiple pregnancy
Chorioamnionitis mx
if pre viable age - TOP
viable age - must deliver to protect mother
Abx - ampicillin, gentamicin, metronidazole
Ddx for abdominal pain in pregnancy
<24 weeks: round ligament strain, ectopic, miscarriage, septic abortion, ruptured CL cyst
> 24 weeks: braxtonhicks, PTL, labour, placental abruption, chorioamnionitis, pre eclampsia
pregnancy related: UTI, cholestasis, GORD
other: PUD, appendicitis, renal calculi, AAA, aortic dissection
pathophysiology of rhesus disease of newborn
○ Rh -ve mother & Rh +ve foetus –> sensitisation occurs –> mother forms Rh antibodies after exposure to Rh+ blood (usually occurs subsequently to exposure in a first pregnancy) –> in subsequent pregnancies Rh antibodies cross the placenta and bind to foetal RBCs –> haemolysis
Sensitisation events - normal delivery, miscarriage, termination, ectopic, abdominal trauma, antepartum haemorrhage
risks of NSAIDs in pregnancy
premature closure of ductus arteriosus
possible increase in miscarriage (inhibits prostaglandin)
foetal renal impairment
MgSO4 dosing
4g over 15-30 minutes
1g/hr after that for 24 hours
