Antenatal Foetal monitoring

Question 1

What are diagnostic tests for foetuses? (not monitoring tests) (3)

Answer 1

amniocentesis
chorionic villus sampling
cordocentesis

Question 2

monitoring tests for foetus?

Answer 2

fetal movements
growth assessment
dopplers
CTG (cardiotocograph)

Question 3

what is mostly used for low risk pregnancies?

Answer 3

fetal movements
(maternal, subjective)
growth charts (not USS)

Question 4

what % of mothers report reduced fetal movements prior to stillbirth?

Answer 4

50%

Question 5

how is fetal heart assessed in low risk and high risk pregnancies?

Answer 5

low: pinard & sonicaid
high: CTG for 40 minutes (don’t strap a low risk pregnancy to the bed)

Question 6

growth assessment in low risk and high risk?

Answer 6

low:
- customised growth chart
- symphio-fundal height by tape measure (SFH)
- random error around 10%
- customised by ethnicity, maternal BMI, previous size of fetuses, age
- every 2-3 weeks

high: USS for fetal growth
- estimated fetal weight by USS (EFW)

also use USS for:
polyhydrimnios
obesity
twins
fibroids

Question 7

when and why and on what are dopplers used?

Answer 7

high risk pregnancy
- to predict maternal outcomes (pre-eclampsia etc)

• umbilical artery
• middle cerebral artery
• ductus venosus (used in v preterm babies, poor outcomes, placental insufficiency)

Question 8

how should mothers assess fetal movements?

Answer 8

any CHANGE in normal movements

Question 9

how can CTG get things wrong

Answer 9

sometimes cannot differentiate fetal/maternal HR, can overestimate a brady fetal HR by combining with maternal HR (eg 80+80)

pinard is more reliable

Question 10

indications for doppler?

Answer 10

if baby is small, big, or at risk of stillbirth

Question 11

what are you checking for with umbilical doppler

Answer 11

that end-diastolic flow/velocity is high enough

ie placental sufficency

Question 12

if a 26 week fetus has low end-diastolic flow, what to do?

Answer 12

the baby won’t make term, but wait until end-diastolic flow is absent, before delivery to maximise outcomes

steroids
magnesium

Question 13

why measure MCA doppler

Answer 13

because if blood flow bad, baby pushes blood flow to brain

Question 14

how to act on abnormal ductus venosus doppler?

indication?

Answer 14

act immediately, predictor of poor outcome & fetal acidosis
deliver within 24 hours.

indication - if <34 weeks and abnormal MCA and end-diastolic flow