Antenatal Care

Question 1

What are some Pre-pregnancy Counselling Steps you should take in women?

Answer 1

• Folate = 500µg for 3mo before pregnancy (5mg if esp. ↑risk – e.g. anticonvulsant medication, Hx of NT defect)
• Avoid teratogens = amoxicillin, ?regular paracetamol, in pre-pregnancy stage.
• Getting pregnant
  
  • Best time to get pregnant = a few days before ovulation, don’t g
  • Intercourse at least every 48h (ideally every 24h)
  • Unlikely to get pregnant in later days of cycle
• Avoid smoking + alcohol + illicit drugs (some bad, cocaine missing limbs)

Question 2

What are the general steps you must take in the first antenatal visit?

Answer 2

1. Confirm Pregnancy
2. Gestational Age
3. Screen for Problems
4. Management of any problems
5. General Advice
6. Booking

Question 3

How do you confirm the pregnancy in the first antenatal visit?

Answer 3

• history
  
  • missed period
  • urinary frequency
  • nausea
  • breast tenderness (esp. sore nipples)
• Examination
  
  • uterine enlargement - usually can’t tell until approximately 8 weeks
• Investigations
  
  • urine HCG (unreliable - cross reacts with LH)
  • serum beta-HCG (approximately 100% reliable - always do)

Question 4

How do you determine the gestational age of a fetus?

Answer 4

• US = most accurate
  
  • 6-12weeks = crown rump length (CRL) +/- 3 days
  • 12-20weeks = biparietal diameter (BPD) +/- 7 days because fetus can flex and extend.
• Menstrual dates
  
  • Naegele’s rule
    
    • 9 months + 1 week from first day of LNMP
    • adust up and down if cycle is longer/shorter than 28 days
    • not reliable is cycle isn’t consitent
      
      • length of luteal phase
      • follicular phase varies.

Question 5

What do you have to screen for in terms of investigations?

Answer 5

• FBE:
  
  • Hb, Platelets, MCV
  • thalassemia (low MCV)
  • anaemia - autoimmune thrombocytopenia common
• Blood group + Ab screen (cross and destroy RBC)
  
  • transfusion dependent
• Microbiology:
  
  • Rubella - know if she seroconverts
  • Varicella - hyper-immune IVIG
  • Syphillis - penicillin
  • HBV - vaccinate child, IVIG for child
  • HCV - avoid procedures (scalp electrodes not done in labour)
  • HIV - no breastfeeding, c-section, antiviral chemo
• Urine MSU
  
  • UTI - asymptomatic bacteruria if untreated.
• Pap smear
  
  • don’t progress till puerpernum
• Imaging
  
  • 12 - nuchal translucency
  • 19 week scan - morphology

Question 6

What is some general advice for pregnancy?

Answer 6

• diet
  
  • nutrition (avoid low GI, complex carbohydrates, iron sources)
  • listeria (avoid food:
    
    • chicken,
    • soft cheese,
    • raw egg = mayo and royal icing,
    • soft serve ice cream
    • causes miscarriage and still birth
• Mineral + vitamine supplementation
  
  • folate (continue during pregnancy as multivitamin - neural tube pre but often benefits during).
  • Fe
  • Calcium and Vitamin D (only recommended to increase risk, winter, dark skin) - work together (1000 tab if together, may want 1500).
  • iodine? Melbourne is iron deficient, recommendation need it during pregnancy.
  • multivitamin? B6 and B12 (elevit)
• Exercise
  
  • moderate good
  • strenous isn’t good - hypoxia, smaller baby.
• Stop smoking
  
  • IUGR
  • increased perinatal mortality
• Alcohol
  
  • heavy consumption (>2std teratogenic)
• Sex
  
  • no harm
• Working
  
  • most choose to cease work around 34 weeks, a few advised to cease earlier
• Medication
  
  • paracetamol and maxalon (nausea) and penicillin okay
• Flu vaccine
  
  • safe anytime
  • pertussis vaccine, parvovirus immunity?

Question 7

Who should you refer to after the first antenatal visit?

Answer 7

• public hospital normal risk - midwives
• GP shared risk - GP ostetrician
• high risk - Obstetrician, subspecialist

Question 8

Subsequent Antenatal visits? What should you look out for?

Answer 8

• Look for:
  
  • Pre-eclampsia
    
    • HTN
    • proteinuria
    • oedema
  • Placental insufficiency
    
    • poor fetal movement (approx 19 weeks)
    • poor growth
• Visit freqency
  
  • <28 weeks every month
  • 28-36 weeks every 1-2 weeks
  • >26 weeks every week
• Hx:
  
  • oedema and headaches
• Ex:
  
  • weight gain
  • BP (seated, R arm, level of heart, Korotkoff phase 5 - disapear not muffling)
  • Fundal height (symphysis pubis to top of uterus - absolute)
  • Lie, presentation, station (head first? cephalic vs breech)
  • auscultation
  • urinalysis (protein) - important
• Ix:
  
  • 28 weeks = FBE + OGTT +/- anti-D if RhD -
  • 36 weeks = repeat FBE if Hb low, GBS swabs, anti-D administration if needed

Question 9

Timing of birth?

Answer 9

• timing:
  
  • median is 40 weeks LMP (38 weeks from conception)
  • 1/400 have perinatal death from beyond 38 weeks
• Mode:
  
  • ideally vaginally
  • C section if
    
    • breech
    • placenta privia
    • previous c-section ( 1 in 200 risk of death and disability)

Question 10

What is the AFI? What could it indicate?

Answer 10

Amniotic fluid index:

• >20 = polyhydramnios
  
  • maternal:
    
    • diabetes
  • Baby:
    
    • placental insufficiency
    • oesophageal atresia
• <5 = oligohydramnios
  
  • kidney problems
  • leaking (rupture)

Question 11

How would you consel a women who is not immune to rubella after a 1st trimester screen?

Answer 11

• avoid contact with any person who has a rubella rash for 7 days after rash onset
• MMR following birth
• restrict contact of people with probable, confirmed or suspected rubella for 6 weeks (2x the incubation period).

Question 12

What is symphyseal fundal height used for? What is its significance?

Answer 12

Symphyseal Fundal Height:

• assessment of fetal growth - top of uterus to top of the pubic symphysis.
• measured in centimeters and roughly corresponds to gestational age in weeks (16-36weeks)
• Landmarks:
  
  • 12 weeks - pubic symphysis
  • 24 weeks - umbilicus
  • 36 weeks - xiphoid process or sternum
  • 37-40 weeks - regression of fundal height (36-32).
• later in pregnancy = less accuracy