Small and Large for Dates Flashcards
what are the 3 main causes of a SGA baby
prematurity
constitutionally small
intra-uterine growth restriction
preterm delivery is classified as birth before how many weeks
37 weeks
outline some of the causes of prematurity
infection
over distension due to multiple pregnancy and polyhydramnios
vascular - placental abruption
cervical incompetence
a SGA foetus is below which centile on growth charts
below 10th centile
list some of the minor risk factors for IUGR
maternal age between 35 and 40 smokes 1-10 cigarettes a day BMI <20 low fruit pre-pregnancy previous pre-eclampsia pregnancy interval <6 months or >60 months
list some of the major risk factors for IUGR
maternal age >40 smokes >10 a day previous SGA baby chronic hypertension renal impairment anti-phospholipid syndrome BMI >35 known large fibroids
what causes a symmetrical IUGR
something affecting the whole foetus - chromosomal abnormalities, TORCH infections
what causes an asymmetrical IUGR
a placental defect, all the nutrients goes to the foetus’ head to preserve brain development over other organs.
conditions such as pre-eclampsia, malnutrition and chronic hypoxia
how is a woman with a single major risk for IUGR managed
umbilical artery doppler from 26 weeks to assess foetal size
how is a woman with 3 minor risks for IUGR managed
umbilical artery doppler from 24 weeks to assess foetal size
when is delivery usually planned for a SGA foetus
37 weeks if no umbilical artery doppler abnormalities
what drugs are given to improve a SGA foetus’ maturing after birth
corticosteroids to improve lung maturity
define a LGA foetus
estimated foetal weight >90th centile
symphyseal fundal height will be more than 2cm for gestational age
list the causes of LGA foetus’
polyhydramnios
multiple pregnancy
macrosomia
wrong dates if late booker
list some of the main complications of LGA
maternal anxiety
shoulder dystocia
post partum haemorrhage
what is polyhydramnios
excessive amniotic fluid, amniotic fluid index >25cm and the deepest vertical pool >8cm
what causes polyhydramnios
maternal diabetes
foetal anomaly - cannot swallow enough fluid
monochorionic twin pregnancy
what are the signs and symptoms of polyhydramnios
abdo discomfort, PPROM, preterm labour, cord prolapse
malpresentation, shiny tense abdomen, inability to feel foetal parts
what is the difference between monozygotic and dizygotic pregnancies
monozygotic - splitting of single fertilised egg
dizygotic - fertilisation of 2 ova by 2 sperm
chronicity refers to what
how many placentas in a twin pregnancy
how is chronicity assessed
ultrasound, assesses the shape and thickness of the membrane
how are triplets delivered
c-section
which type of twin pregnancy is always delivered by c-section
monochorionic mono amniotic due to risk of cord entanglement
what is given after the delivery of twin 1 to aid the contractions for the delivery of twin 2
syntocinon
what is twin-twin transfusion syndrome
disproportionate blood supply to foetuses in monochorionic pregnancies – as a placenta is shared the blood supply can flow from the donor twin to recipient twin causing complications for both
outline the complications for the donor and recipient twin in TTTS
donor - reduced blood volume and urine output, poor growth, oligohydramnios
recipient - increased blood and urine output, polyhydramnios, polycythaemia, heart failure
how is TTTS managed
fetoscopic laser ablation before 26 weeks
aim to deliver between 34-36 weeks
