Abnormal Growth

Question 1

How is GA determined?

Answer 1

LMP
mean gestational sac
CRL
BPD, FL, AC, HC

Question 2

Small for GA babies have a birth weigh below the _____ __________.

Answer 2

10th percentile

Question 3

What causes SGA?

Answer 3

genetics
IUGR
*most SGA babies are small bc of fetal growth problems that occur during pregnancy

Question 4

IUGR:

Answer 4

occurs when fetus doesn’t receive the proper necessary nutrients and oxygen needed
can occur anytime in pregnancy
early onset is due to chromosomal abnormalities, maternal dx or severe placental problems

Question 5

What are some maternal factors that can contribute to SGA or IUGR?

Answer 5

high BP
chronic kidney dx
adv diabetes
heart/respiratory dx
malnutrition/anemia
infection
substance use
cigs

Question 6

What are uterus/placental factors that contribute to SGA or IUGR?

Answer 6

dec blood flow in uterus + placenta
placental abruption
placental previa
infection in tissues around fetus

Question 7

What are fetal factors that contribute to SGA or IUGR?

Answer 7

multiple gestations
infection
birth defects
chromosomal abnormalities

Question 8

Perinatal mortality rate is _____ higher than infants born with appropriate weight for GA; the risk of asphyxia is _____ higher.

Answer 8

8x

7x

Question 9

Babies w/ SGA or IUGR may have problems at birth including:

Answer 9

dec oxygen levels
low Apgar scores
meconium aspiration
hypoglycemia
difficulty maintaining normal body temp
polycythemia

Question 10

What are most cases of IUGR caused by?

Answer 10

placental insufficiency

either primary or secondary (hypertension, collagen vascular dx, poor nutrition or substance abuse)

Question 11

IUGR can either be __________ or ___________

Answer 11

asymmetrical or symmetrical

Question 12

IUGR is normally used to refer to small fetuses with a higher risk of?

Answer 12

utero deterioration, stillbirth and overall poorer perinatal outcome

Question 13

Symmetrical SGAs-

Answer 13

all measurements (HC, length, weight) are reduced. Usually caused in early pregnancy (chromosomal abnormalities, rubella)

Question 14

Asymmetrical SGAs-

Answer 14

only have a weight reduction, with a normal sized head circumference and body length
Insults that appear in the 3rd trimester (hypertension)

Question 15

The most common cause of early onset (symmetrical) IUGR is what? What’s the second most common?

Answer 15

chromosomal abnormality (aneuploidy)

second is fetal infection

Question 16

Which type of IUGR is more common?

Answer 16

asymmetrical (2/3rds)

Question 17

Why is the head size of fetus with asymmetrical IUGR normal?

Answer 17

blood flow is directed towards the fetal brain at the expense of the other organ systems

Question 18

What is the single best parameter for diagnosing asymmetrical IUGR?

Answer 18

AC measurement

if AC growth is less than 1cm in 14days this indicates IUGR (after appts repeated 2wk intervals)

Question 19

What are non-specific findings of IUGR?

Answer 19

oligohydramnios
placental senescence (grade 3 placenta before 36wks)
delayed sonographic appearance of the distal femoral ossification center

Question 20

Macrosomia refers to fetuses:

Answer 20

above the 90th percentile for GA
most often defined as fetal weight >4000g
most complications occur with fetuses weighing more than >4500g

Question 21

What’s the most common risk factor for macrosomia?

Answer 21

maternal diabetes

Question 22

What are factors of macrosomia?

Answer 22

diabetes*
previous delivery of a large infant
maternal obesity
tall mother
excess weight gain during pregnancy
multiparity
adv maternal age >35
post term delivery

Question 23

Large fetuses have a higher incidence of ?

Answer 23

perinatal morbidity and mortality

birth trauma- shoulder dystocia, fractures, facial + brachial plexus palsies, birth asphyxia, prolonged pregnancy