Normal development of pregnancies

Question 1

When does ovulation occur?

Where does fertilisation occur?

When does implantation occur?

Answer 1

• 14 days before the end of the cycle
• in the fallopian tubes
• day 23

Question 2

what happens to levels of HCG?

when can they first be detected?

what is the point in B-HCG in pregnancy?

what is its side effect?

Answer 2

• rise rapidly (doubling every day) until 10 weeks
• 4 weeks after last menstrual period
• continues to stimulate the corpus lute to produce progesterone, vital to foetal survival, NO pituitary/ hypothalamic input
• morning sickness

Question 3

what does progesterone cause?

Answer 3

• uterine quiescence
• respiratory changes
• immune system depression to not reject foetus

Question 4

what roles does the placenta perform before 12 weeks?

Answer 4

• gas exchange
• nutrient waste/ transfer
• steroidogenesis

Question 5

what may cause a foetus to be large/ small for dates?

Answer 5

• maternal height and weight
• foetal sex/ genetic/ inherited conditions
• social class, nutritional status, altitude
• pre-existing disease
• pregnancy related disease (DM and HTN)
• foetal: nutrition (IUGR), teratogens, infection

Question 6

What is the concept of head sparing?

Answer 6

• foetus experiencing reduced nutrition, head growth prioritised over abdomen, leading to asymmetric growth

Question 7

how do you distinguish between IUGR and constitutionally small?

Answer 7

• if baby remains in same growth centile throughout then constitutionally small
• drop in baby growth indicates IUGR

Question 8

Who does the biophysical profile include?

Answer 8

• Foetal breathing movements
• Foetal movements
• Foetal tone
• Amniotic fluid levels
• CTG for monitoring

Question 9

What is measured in a doppler study?

what should you find?

Answer 9

• pulsatility
• resistance
• low resistance, end diastolic flow

Question 10

if you have an absent or reversed end diastolic flow what may thins indicate? (3)

Answer 10

• pre-eclampsia
• IUGR
• placental abruption

Question 11

what should you do if symphyseal-fundal height is lower than gestation and what is threshold?

Answer 11

• > 2cm less than gestation

- refer for USS, serial USS measurements

Question 12

If USS shows small baby (<10th centile) what should you do?

Answer 12

• UA Doppler
• if normal resistance + growing foetus then just constitutionally small
• if high resistance and foetal compromise: deliver baby, give steroids and daily CTG

Question 13

what are reasons for LGA?

Answer 13

• (gestational) diabetes

- obesity

Question 14

when will the mother typically perceive foetal movements?

what happens to movements from then on?

How long should there not be a period of no foetal movement for?

what advice should you give women who have RFM?

Answer 14

• 18-20 weeks
• plateaus at 32 weeks, NOT reduced.
• > 90 mins
• if unsure, lie in left lateral for 2 hours
• attend unit if experiencing <10 movements in 2 hours

Question 15

if suspecting stillbirth what would you do for risk evaluation?

Answer 15

• multiple RFM visits
• known IUGR
• DM
• HTN
• extremes of maternal age
• primiparity
• smoking
• placental insufficiency
• obesity
• poor past obstetric history

Question 16

what should happen to mother if perceived RFM?

Answer 16

• CTG (beyond 28 weeks) for 20 mins
• USS
• doppler if before 24 weeks
• auscultate foetal heart

Question 17

What is the risk of having a prolonged pregnancy?

Answer 17

• increased chance of stillbirth
• risk of encephalopathy
• meconium passage

Question 18

What should be done at 41 weeks to promote pregnancy?

Answer 18

• Stretch and sweep
• Artificial rupture of membranes
• Propess
• Syntocin, Syntometrin