Small for Dates Pregnancy Flashcards
What may cause a baby to be small for dates?
- pre term delivery
- small for gestational age
- IUGR/FGR
- Constitutionally small
What is preterm delivery?
delivery before 37 weeks gestation
- extreme preterm: 24-27+6 weeks
- very preterm: 28-31+ 6 weeks
- moderate to late preterm: 32- 36+6 weeks
When is viability defined in the UK?
24 weeks
when does your baby have a 40% chance of survival?
24 weeks
What is the aetiology of preterm birth?
- infection
- over distension
- multiple pregnancy
- polyhydramnios
- vascular
- placental abruption
- intercurrent illness
- pyelonephritis/UTI
- appendicitis
- pneumonia
- cervical incompetence
- idiopathic
What are the risk factors for preterm birth?
- Previous PTL (20% risk x1, 40% risk x2)
- multiple pregnancy (50%)
- uterine anomalies
- age (teenager)
- parity 0 or >5
- ethnicity
- poor socio-economic status
- smoking
- drugs (especially cocaine)
- low BMI <20
what percentage of preterm births are planned?
25%
what percentage of preterm births are due to premature rupture of membranes?
20%
what percentage of preterm births are due to emergency event?
25%
What is IUGR/FGR?
failure to achieve growth potential
What is low birth weight?
Birth weight below 2.5kg regardless of gestation
SGA fetus is defined as an estimated fetal weight or abdominal circumference meaurement below the __th centile.
SGA fetus is defined as an estimated fetal weight or abdominal circumference meaurement below the 10th centile.
What are the two broad divisions of IUGR and why do they occur?
Symmetrical- may point to a chromosomal abnormality or in utero infection
Asymmetrical- placental reasons, baby is diverting blood to head to protect brain growth over other less vital organs.
How do we identify a SGA foetus?
Antenatal risk factors
Screening during antenatal care
A single major risk factor of SGA means that we should be formally measuring and monitoring fetal growth by means of ultrasound to estimate fetal size from 26-28 weeks, and at regular intervals until approximately __ weeks. In practice this usually means minimum scans at __, __ and __ weeksgestation. This is what we usually mean if you here us say “serial growth scans”.
A single major risk factor means that we should be formally measuring and monitoring fetal growth by means of ultrasound to estimate fetal size from 26-28 weeks, and at regular intervals until approximately 36 weeks. In practice this usually means minimum scans at 28, 32 and 36 weeksgestation. This is what we usually mean if you here us say “serial growth scans”.