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Y2 LCRS 1 - RDA > Fetal Growth > Flashcards

Flashcards in Fetal Growth Deck (26)
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1

Define fetal growth

The increase in mass that occurs between the end of the embryonic period and birth

2

What parameters are used to estimate fetal weight?

Biparietal diameter (BPD), Head circumference (HC), abdominal circumference (AC), Femur length (FL).

3

Why are USS used in pregnancy?

Main role is to assess the wellbeing of the fetus. Assessing growth trends. Predicting the need for premature delivery. Date a pregnancy

4

What other method can be used to assess fetal growth? (other than USS)

Symphysis fundal height. ( palpate abdomen to find the pubic symphysis and top of the uterus).

5

Name 3 factors that can mean an inaccurate EWF using symphysis fundal height.

Underestimation- wrong date of last period, Small for gestational age, oligohydramines, baby lying horizontally.

overestimation- wrong date for last period, multiple preganacies, large gestational age, polyhydramines, high BMI mother, fibroids.

6

Define SGA

Birth weight <10th centile

7

What maternal factors influence foetal growth?

Economic status. Age (<16 and >35), Abnormal BMI, smoking, alcohol, diet, anaemia, hypertension, depression, illness/chronic disease, drugs and toxins.

8

In general is the first or second child larger?

The second child.

9

What cellular changes normally occur during the course of gestation?

Week 4-20= hyperplasia
week 20-28= hyperplasia and hypertrophy
week 28-40= hypertrophy dominates

10

What fetal hormones are involved in regulating fetal growth and development?

Cortisol, Thyroxine, insulin and pituitary growth hormone

11

What hormones are responsible for tissue differentiation?

Cortisol and thyroxine (is also responsible for accretion, which is the increasin in number of layers of cells)

12

Define IGUR

Failure of an infant to achieve its predeterimed genetic potential for a variety of reasons.

13

Why does IGUR usually develope in the 2nd and 3rd trimesters?

As this is when the majority of fetal growth occurs and influencing factors have the biggest impact.

14

what is the role of fetal insulin?

Modifies IGF expression IGF1--> IGF2, increases mitotic drive and increases tissue availabilty for accretion

15

Name 2 fetal factors impacting fetal growth

Multiple preganacies, structural abnormalities, genotype, gender and chromosomal abnormalities.

16

Name 4 placental factors that can cause IUGR

Impaired trophoblast invasion, partial abruption/ infarction, chorioamnionitis, placental cyst, placental praevia

17

What usually causes preeclampsia and why is it associated with IUGR?

Deminished remodelling of spiral arteries in the uterus, causing decreased placental blood flow. This decreases the nutrients reaching the baby and restricting growth.

18

Preeclampsia is difficult to treat but what can be done to limit the damage?

Give corticosteriods to baby at birth and balance between early delivery risk and benefits.

19

When are at risk patients screen for IUGR?

at 24 weeks

20

Which centiles are most sensitive and most specific for IUGR/FGR

10th is most sensitive (everyone but some false positives)
3rd is most specific (potentially some false negatives)

21

What is the difference between fetal age and gestational age?

Gestational age is measure from the first day of the mothers last period.
Foetal age is from fertilisation so is usually two weeks less than GA.

22

What are the parameters to define preeclampsia?

Bp raised aboved 140/90 on 2 spearate occasions .4hrs apart.
proteinuria > 0.3g/day after 20 weeks
oedema

23

Define low birth weight and very low birth weight

LBW= <2500g
VLBW=<1500g

24

What are the short term risks associated with FGR?

Respiratory disress
Intraventricular bleed
Sepsis
hypoglycaemia
necroenterocolitis
jaundice
Electrolyte imbalances

25

What tests are done to determine IUGR?

PAPPA <0.3MOM
Uterine atery doppler scan 60-70% loss of function gives abnormal reading

26

which week and baby weight would you aim to deliver a FGR baby after?

>28 weeks and >500g