H/E Lecture 4 Flashcards
(29 cards)
When do bone ossification centers form?
Week 12
When are external genitalia visible with ultrasonography?
About week 12
When does the fetus start swallowing and forming urine?
About week 10
When do respiratory movements begin?
About week 15
When does the fetus begin to recognize sound and light?
Weeks 24-28
What is the greasy coating on baby’s skin and what does it do?
Vernix Caseosa: moisturizes, insulates, lubricates during birth, antibacterial
What holds the vernix in place?
Lanugo: these are fine hairs on the baby’s skin
What is the common height measurement of a fetus?
Crown-rump length (CRL) which is from the bottom to the crown of the head
When during development does height and weight increase the most?
CRL increases the most early on, weight gain increases the most later on.
What is SGA and how is it diagnosed?
Small for Gestational Age: less than 10th percentile in weight for gestational age, but weight for size is normal
What is IUGR?
Intruterine Growth Restriction/Retardation: ,10th percentile weight and <2.5th percentile weight for abdominal circumference
At what point is the embryo called a fetus?
Week 12
Before what gestational age is preterm birth?
before 37 weeks gestational age
Birth at what GA will babies have a reddish appearance?
Before 28 weeks
What is the major cause of death for preterm babies?
respiratory failure
What is the fFN test and when is it appropriate to use?
Fetal Fibronectin: vaginal swab to test for placental adhesive glycoproteins which hold the placenta to the uterus. Tests for preterm delivery risk. Reliable between 22-34 weeks.
What is RDS? And when is a fetus at low, moderate, and high risk for this?
Respiratory Distress Syndrome:
Low>34 weeks
Moderate 28-34 weeks
High <28 weeks
What treatment is available for RDS prenatally and postnatally?
Prenatal: Glucocorticoids (a steroid) are given to the mother to promote surfactant secretion in lung to prevent collapse
Postnatal: CPAP (continuous positive airway pressure) to hold airway open
How do you test for RDS risk?
Lecithin-sphingomyelin ratio test: lecithin should rise relative to sphingomyelin beginning in the 34th week. 2:1=low risk. 1.5:1 and below is a significant risk.
Test is performed through amniocentesis.
At what age is the embryo large enough to see with ultrasonography?
about 5 weeks
What is amniocentesis?
Sampling amniotic fluid with needle and guided by ultrsonography.
Between weeks 14-20 to have enough fluid and not too big a baby.
Retrieves fetal cells for karyotyping.
What is CVS?
Chorionic Villus Sampling: Biopsy of chorionic villus (the villi of the chorion) using a needle and ultrasound
10-14 weeks (amniocentesis preferred after)
Low risk
Less accurate than amniocentesis, but allows for earlier karyotyping.
What is maternal serum screening?
Looking for fetal markers in maternal blood.
alpha-fetoprotein:
abnormal levels indicate neural tube defects, GI defects, Down syndrome.
hCG: indicates molar pregnancy, ectopic pregnancy, choriocarcinoma, and down syndrome
Numerous false positives
What is fetoscopy or fetendo?
Endoscopic procedure where needle with camera is inserted to see fetus. Very risky (5-10% complications) inly used in extreme cases.
