Fetal growth Flashcards
how do you assess how well the baby is growing?
palpate, look, measure (fundus to pubic symphsis)
the palpation of the abdomen is the simplest way to determine the size of the infant- gives you the symphysis fundal height
What is the SFH?
symphysis fundal height.
distance over the abdominal wall from the symphsis to the top of the fundus.
It may be small - they may have the dates wrong, small baby, transverse lie, little fluid. OR the baby is small for the gestational age.
Larger - wrong dates, multiple pregnancies or obesity.
GOOD: as it is inexpensive and simple BUT low detection rate as has many counfounders
What is used to measure the baby now?
Ultrasound. After 14 weeks
TAKE: BDP(biparietal diameter), HC(head circumference),AC (abdominal circumference),FL (femur length)- give you the approximate weight
Look at graphs and be worried if it crosses percentiles
ULTRASOUND IS USED TO DATE USING THE CROWN RUMP SIZE AT THE END OF THE FIRST TRIMESTER AS THIS IS WHEN GROWTH IS AT ITS SLOWEST.
Why is it important to accuratley date?
SGA or LGA confusion
inappropraite inductions
steroids in preterm delivery.
What maternal factors affect fetal growth?
Maternal- poverty (less nutrition and education)
age (over 35 = longer labour period and more likely to have complications but younger are more likely to drink and smoke)
drug use(metabolised by the placenta and transmitted to the fetus leading to a greater chance of birth defects, low birth weight and still births)
Alcohol (disruptions in the fetus’ brain + cell development and maturation + CNS maturation)
smoking - nicotine = less blood flow to the fetus , Co reduces the o2 and this can lead to still birth, low birth weight and ectopic pregnancy.
diseases - placenta may not filter out so can inherit this.
diet + physical health - needs adequate nutrition. low iron = anaemia + low calcium = weak bones
prenatal depression - slower fetal growth
environmental toxins - miscarriage, sterility, birth defects.
What fetal hormones are important?
Somatotrophin insulin prolactin FSH/LH etc
Can there be a customised growth chart?
can adjust for maternal height, weight and ethnicity.
What is SGA(small gestational age)?
birth weight less than the tenth percentile
What is IUGR?
failure of the infant to reach it’s predetermined potential due to a variety of reasons.
this is one of the most common identifiable factors in still births.
Why does LBW matter?
not always growth restricted
this is less than 2.5kg at birth. only 7% of live births.
very LBW - less than 1.5kg
extremely LBW - less than 1kg
IMPORTANT AS THOSE WITH A LOW BIRTH WEIGHT ARE AT RISK OF A RANGE OF NEONATAL COMPLICATIONS + COMMODITIES AND MORTALITY (CHD, IHD AND DIABETES)
what are the short and long term sequelae of FGR?
most common for still born babies
resp distress - minimised with steroid injections to the mum
haemorrhage
sepsis
jaundice
electrolyte imbalance
hypoglycaemia
long term issues of fetal programming
What are causes of SGA?
dating problem
normal
fetal problem (5%)- infection or abnormality(chromsomal)
placental insufficency (20%) - reduction in AC/FL, reduced liquor (amniotic fluid), derange dopplers
Why is the placenta?
maintains immunological distance between mum and fetus.
What are concerns in the index pregnancy?
abnormal serum biochemistry reduced symphysis fundal height maternal systemic disease coagulation anterpartum haemorrhage
How can FGR be predicted?
through a good history