Placental Dysfunction

Question 1

What is placental dysfunction?

Answer 1

• it is when the placenta is unable to deliver an adequate supply of nutrients and oxygen to the fetus and thus cannot fully support the developing baby

Question 2

What can be the complication of a true knot in the umbilical cord?

Answer 2

• restricts blood flow to the fetus

Question 3

What are the anatomical variations of the placenta?

Answer 3

• succenturiate lobe
• battledore insertion
• velamentous insertion
• bipartite/tripartite placenta
• circumvallate placenta - opaque thickened ridge is seen on fetal surface due to the doubling back of the membranes, associated with growth retardation

Question 4

What is polyhydramnios?

Answer 4

• can affect around 1.5% of pregnancies
• if severe and the fetus cannot swallow there may be in excess of 2000ml of amniotic fluid
• may be chronic, more common and occurs after 30/40
• may be acute, rare, occurs at 20/40 and may be associated with mono-ovular twins or severe abnormality

Question 5

What are the signs of polyhydramnios?

Answer 5

• uterus is large for dates
• easy ballottment of the fetus
• fetal parts difficult to palpate
• FH muffled
• maternal symptoms - breathlessness, vulval varicosities, oedema and gastric problems

Question 6

What are the causes of polyhydramnios?

Answer 6

- fetal causes
      —> multiple pregnancy
      —> CNS anomalies 
      —> GI anomalies 
      —> haematological anomalies 
      —> skeletal anomalies 
      —> chromosomal anomalies
      —> intrauterine infections 
- maternal causes 
      —> diabetes 
      —> Rhesus isoimmunisation

Question 7

What are the complications of polyhydramnios?

Answer 7

• unstable lie
• malpresentation
• cord presentation and prolapse
• preterm labour
• preterm ROM
• PPH

Question 8

What is oligohydramnios?

Answer 8

• defined as <500ml of amniotic fluid at term, however may be much less
• affects 4% of pregnancies

Question 9

What are the signs of oligohydramnios?

Answer 9

• SGA uterus
• decreased FM’s
• fetus feels compact with parts easily palpated

Question 10

What are the causes of oligohydramnios?

Answer 10

• severe IUGR associated with maternal disease such as hypertension or renal disease
• fetal renal anomalies
• other anomalies
• chronic placental abruption

Question 11

What are the complications of oligohydramnios?

Answer 11

• poor prognosis
• pulmonary hypoplasia affects 60% of those deprived for many weeks
• treatment - amnioinfusion but not widely used, delivery of infant

Question 12

What is IUGR?

Answer 12

• fetus that fails to reach it’s personal growth potential
• SGA
• essential substrates for growth are oxygen, glucose and amino acids
  —> any decrease in substrate availability due to pathological conditions affecting mother, placenta or fetus will result in poor growth

Question 13

What is asymmetric fetal growth restriction?

Answer 13

• fetal weight is reduced out of proportion to length and head circumference
• little subcutaneous fat
• usually maternal in origin
• growth may ‘tail off’ having been normal

Question 14

What maternal conditions can cause IUGR?

Answer 14

• hypertension
• chronic renal disease
• sickle cell anaemia
• severe cardiac disease
• severe malnutrition
• smoking
• alcohol ingestion

Question 15

What fetoplacental problems can cause IUGR?

Answer 15

• chromosomal abnormalities
• intrauterine infections
• h/o IUGR
• multiple pregnancy
• placenta praevia
• placenta infarcts

Question 16

How is IUGR diagnosed and managed?

Answer 16

• fetal weight - uss
• Doppler velocimetry abnormalities
• measuring subcutaneous fat
• fetal biophysical profile
• is baby better in or out?
  —> steroids
  —> ctg
  —> paed at delivery
  —> blood gases

Question 17

What is the role of the midwife?

Answer 17

• support
• discussion with family/translation of medical terms
• work closely with MDT
• close monitoring of mother and baby
• visit NNU with parents
• preparation for birth