fetal growth

Question 1

what factors can affect fetal growth?

Answer 1

many, including:

a. glucose and amino acids that freely cross the placenta
b. insulin and human growth hormone
c. gestational diabetes can significantly increase fetal weight, but is detectable with a glucose tolerance test
d. risk factors for intrauterine growth retardation (IUGR)

Question 2

what is fetal weight with IUGR?

Answer 2

within lowest 10% of normal

Question 3

what are risk factors for IUGR?

Answer 3

cigarette smoking during the last 6-8 weeks
multiple fetuses
poor nutrition
placental dysfunction/abnormal uteroplacental circulation

Question 4

major hallmarks at 12 weeks of development

Answer 4

a. primary ossification centers appear in long and cranial bones
b. external genitalia are visible by ultrasound
c. urine is produced and excreted into the amniotic fluid

Question 5

events from 13-16 weeks

Answer 5

a. eyes move anteriorly but do not open until 26 weeks
b. ears move cranially to their final position
c. beginnings of fetal movement

Question 6

what are lanugo and vernix caseosa?

Answer 6

appear in 13 to 16 weekis. lanugo is fine hair and vernix caseosa is white, fatty substance secreted by sebacious glands. lanugo helps hold the vernix to the skin. vernix caseosa protects the fetal skin from amniotic fluid.

Question 7

where does erythropoeisis occur throughout the fetus?

Answer 7

a. in the fetal liver for several weeks at start of fetal period
b. it then occurs in the spleen until approximately week 28
c thereafter, it occurs in the bone marrow

Question 8

quickening?

Answer 8

early fetal movements felt by mother begins to occur around weeks 17-20

Question 9

when is lung surfactant made? what is its purpose?

Answer 9

at approx 24 weeks. it decreases lung air sac surface tension and therefore allows opening of the air sacs this significantly increases premature fetal viability

Question 10

five common fetal diagnostic tests

Answer 10

amniocentesis, chorionic villous sampling, ultrasound, MRI, quad marker screen

Question 11

amniocentensis

Answer 11

withdrawal of 30-40cc of amniotic fluid
tests alpha-tetoprotein (also in maternal blood) for failure of neural tube to close
karyotype for gross chromosomal abnormalities
screen for specific heritable diseases

Question 12

chorionic villous sampling

Answer 12

biopsy of fetal portion of placenta provides cells that can be cultured for karyotyping and more extensive genetic testing

Question 13

ultrasound

Answer 13

monitors formation of organs and skeletal development
used to monitor genera growth my measurement of
a. abdominal circumference
b head circumference
c. femur length
d. foot length

Question 14

Magnetic resonance imaging

Answer 14

for more detailed imaging of organs and structures

Question 15

quad marker screen

Answer 15

typically offered 15th-20th week of pregnancy.
blood sample test for:
lapha-fetoprotein (AFP) a protein produed by the fetal liver
uncongugated estriol (UE): a protein produced in placenta and fetal liver
hCG: a hormone produced by the placenta
inhibin A; a hormone produced by the placenta

Question 16

Quad marker screen is sometimes called Down Syndrome Screen ecause?

Answer 16

down syndrome is associated with low AFP, high UE, high hCG, high Inhibin A