multiple gestation Flashcards
how can multiple gestation occur
> 1 egg released during 1 menstrual cycle
zygote divides after fertilisation -> identical twins
IVF - often transfer >1 embryo to the uterus
what is amnionicity
the number of amnions (inner membranes) that surround babies in a multiple pregnancy
1 amnion (all babies share a sac) - monoamniotic 2 amnions - diamniotic
what is chorionicity
number of chorionic (outer) membranes that surround babies in a multiple pregnancy
1 membrane - monochorionic
2 - dichorionic
what are the 3 types of twin pregnancies
dichorionic diamniotic (DCDA) - can happen from 2 separate eggs fertilised by separate sperms or can happen from an early division of the zygote
MCDA
MCMA
how to determine chorionicity and amnionicity
fetal USS
what is the lambda sign indicative of
2 placentas - DCDA twins
what is the T sign indicative of
single placenta
MCDA twins
what are some maternal complications of multiple births
preterm labour hyperemesis anaemia in pregnancy HT gestational diabetes PPH
fetal complications of multiple births
growth restriction
prematurity
increased birth complications
increased perinatal mortality/morbidity
name complications of monochorionic twins
twin to twin transfusion syndrome - blood moves from one baby to the other due to a shared placenta, one baby loses blood (donor twin)
selective growth restriction
twin anaemia polycythaemia sequence
twin reversed arterial perfusion (TRAP)
single twin death
antenatal care for multiple births
routine care incl. trisomy 21 screening/structural scans
specialist clinic - regular scans for growth and complications
DCDA require at least 8 AN visits
MC require at least 11 AN visits
monitor BP at every visit, commence oral iron if required
when are multiple births delivered
aim for delivery at:
DCDA - 37wks
MCDA - 36 wks
triplets - 35wks
earlier if any maternal/fetal complications
mode of delivery for multiple births
twins - vaginal/CS, if 1st twin isn’t cephalic - offer CS (1/3 of all twins are CS)
triplets - CS
