Multiple Pregnancy (NICE +GTG) Flashcards
How long should scan appointments be for multiples?
45 mins for anomaly scan.
30 mins for growth scans.
If a woman presents after 14/40, how should chronicity be determined?
- Number of placental masses.
- Membranes and the thickness.
- Labmda/T sign.
- Discordant foetal sex.
If chronicity cannot be determined, how should the pregnancy be treated?
As mono-chorionic.
When estimating gestational age, should the larger or smaller twin be used? Why?
The larger twin should be used to determine gestational age to avoid over-estimating FGR.
How is chronicity assessed?
- No. placental masses.
- Presence of amniotic membranes and thickness
(T and Lambda sign)
How should 3D scans be used to determine chronicity?
3D scans should not be used to assess chronicity.
When should an additional FBC be carried out in multiple pregnancy and why?
20-24/40
To detect early anaemia.
In Monochorionic twins, when should US assessment be carried out?
11-14/40 dating and chronicity.
18-22/40 anomaly and growth.
2 weekly growth scans after anomaly US (i.e. from 22/40).
When should uncomplicated DCDA twins aim to be delivered?
37/40
When should uncomplicated MCDA twins be delivered?
36/40
When should uncomplicated TCTA triplets aim to be delivered?
35/40
When should uncomplicated DCTA / MCTA triplets be delivered?
35/40
Can FASP be offered in twin pregnancies?
Yes.
Can FASP be offered in triplet pregnancies?
Yes, but:
- greater chance of trisomy in triplets.
- increased false positive rate of FASP.
Can foetal fibronectin be used to assess risk of pre-term labour in multiple pregnancies?
Foetal fibronectin should not be used alone.
Is discordance in NT or CRL in first trimestser an accurate predictor of 2nd and 3rd trimester discordance?
No.
When can US for FGR and feto-feoetal transfusion syndrome be used in DCDA twins?
2nd and 3rd trimester.
(I.e. not in 1st trimester).
How often should uncomplicated DCDA twins have a growth scan?
4 weekly from 24 weeks.
How is EFW Discordance calculated?
((EFW largest - EFW smallest)/(EFW largest)) *100
At what EFW discordance be referred to a tertiary unit?
Discordance 25% or more
AND one EFW 10th centile or less.
What 3 conditions should be screen for at every US in monochorionic twins?
- Feto-feotal transfusion syndrome.
- FGR.
- TAPS (twin anaemia polycythaemia sequence).
How is feto-foetal transfusion syndrome identified?
What is the ongoing monitoring?
One baby has DVP <2cm and the other baby has DVP >8cm (before 20/40) or >10cm (after 20/40).
increase to weekly US if either DVP is >4cm.
All mono twins should have US every 2 weeks from 16/40.
What is twin anaemia polycythemia sequence?
A form of TTTS that can complicate mono pregnancies.
Unequal blood counts between babies.
Caused by a few small AV anastomoses in the placenta.
Causes recipient twin becoming polycythemic and donor becoming anaemic.
What is seen in the amniotic fluid levels between babies suffering with TAPS?
Amniotic fluid levels are equal.
How is TAPS staged?
Leiden Staging System (includes maximum blood flow speed through MCA).
Is the routine use of vaginal progesterone recommended to prevent preterm birth in multiple pregnancies?
No, there are no recommendations about vaginal progesterone as routine use in preventing preterm birth in multiples.
What is the rate of spontaneous delivery in twins <37/40?
60%
From what gestation is there an increased risk of foetal death in DCDA twins?
From 38/40
(therefore deliver from 37/40)
From what gestation is there an increased risk of foetal death in MCDA twins?
37/40
(therefore deliver from 36/40)
From what gestation is there an increased risk of foetal death in MCMA twins?
34/40
(Therefore deliver 32-33+6)
From what gestation is there an increased risk of foetal death in triplet pregnancies?
36/40
Therefore deliver at 35/40
What is the rate of spontaneous delivery before 35/40 in triplet pregnancies?
75% before 35/40
What is vaginal delivery safe for multiples?
DCDA twins: >32/40, if no obstetric CI, cephalic first twin and no significant size discordance.
Offer LSCS to MCDA and MCMA unless the head is on the perineum.
What is the risk of requiring LSCS for the second twin after a vaginal delivery of the first twin?
10%
From what gestation can FSE be appled?
34/40
Can physiological management of the third stage of labour be offered after vaginal twin delivery?
NO! Therefore discuss active management early in pregnancy.
