First Trimester Flashcards
Nuchal translucency
fluid collection vis. behind the fetal neck
most accurate from 11-14 wks
> 3mm is abnormal
pseudocyesis
a psychological condition in which a pt. believes she is pregnant, when she isn’t
hyperemesis
excessive vomiting that leads to dehydration and electrolyte imbalance
assoc. with trophoblastic disease, multiple pregnancies, and ovarian hyperstimulation
normal hCG levels
double every 30-48 hrs
peak at the 10th gest. wk
begin to decline until the 18th gest. wk
then level out for remainder of pregnancy
gestational sac and yolk sac (should be measured how?)
inner to inner
fertilization
mature ovum is released at Day 14
fertilization occures 1-2 days after ovulation
decidual reaction “double decidua sign” (layers)
deciduas capsularis: covers blastocyst
decidual basalis: between conceptus and UT wall
decidual parietalis “decidua vera”: covers the rest of UT
secondary yolk sac
seen w/i first trim. produces AFP transfers nutrients hematopoiesis connected to fetus by vitelline/omphalomesenteric duct becomes part of the primitive gut liver takes over by 8th gest. wk.
abnormal NT
> 3 mm
Indicates: Trisomy 21, 18, Turner’s Syndrome, congestive heart failure
measured inner to inner
most common site for an ectopic
ampulla of the fallopian tube
(isthmus = 2nd most common site)
(interstitial = most dangerous)
Other locations: cervix, ovary, and fimbraie
choriocarcinoma
most malignant form of trophoblastic disease with possible metastasis
result of malignant growth of hydatidiform molar pregnancy
common sites for metastasis = liver, lungs, and vagina
threatened AB
presents as low FHR
vaginal bleeding before 20 wks gest.
closed cervix
inevitable AB
presents with low-lying gest. sac and open internal os of cervix
vaginal bleeding with dilated cervix
abnormal positions of the fetal heart
levocardiac = to left mesocardiac = to right dextrocardiac = heart lies in right side, with apex pointing towards the right
mitral valve
vs.
tricuspid valve
left side
vs.
right side
fetal hydronephrosis renal pelvis measurement
renal pelvis > 10 mm
proximal tibial epiphysis
usually seen in the 37th wk.
cases of heterotopic pregnancy occur in approximately 1 in how many?
1 in 30,000
normal yolk sac measurement
= 6 mm
prosencephalon
forebrain
crainosyntosis
premature fusion of cranial bones/sutures
bregma
anterior fontanelle when filled with bone
lambda
posterior fontanelle when filled with bone
function of the choroid plexus
mass of cells responsible for producing the Cerebrospinal fluid in the fetus
mesocephalic
normal sized head
atrial septum
vs.
ventricular septum
atrial septum is open to the foramen ovale
vs.
ventricular septum is uninterrupted
fetal blood circulation
half of blood to liver via LPV/umbilical vein
half of blood shunted to IVC via ductus venosus (branch off umbilical vein)
ductus venosum
takes blood from the umbilical vein to the right atrium
the left ventricle connects to what major blood vessel
aorta
the right ventricle connects to what major blood vessel
pulmonary artery
fetal lung maturity can be assessed by using what ratio?
(L/S ratio)
lecithin to sphingomyelin ratio
tested by an amniocentesis
mature lungs with show: increased lecithin and decreased sphingomyelin
foramen ovale
shunts blood from the right atrium to the left atrium
ductus arteriosus
shunts blood from the pulmonary vein to the descending aorta
what valve lies between the left atrium and ventricle?
mitral valve
what valve lies between the right atrium and ventricle?
tricuspid valve
what normal structure of the heart lies within the right ventricle?
moderator band
transcerebellar measurement
correlates with gest. age
grows at a rate of 1 mm per wk. between 14-21 wks
rhombencephalon
hindbrain
cystic structure seen within an embryo during the first trimester
mesencephalon
midbrain
normal NT measurements should not exceed
3 mm
distal femoral epiphysis
seen at 32-33 wks. (not included in measurement)
what anomaly is brachycephaly seen with?
trisomy 21
what is dolicocephaly head shape seen with?
breech presentation
cephalic index
devised to determine normality of fetal head shape
missed AB
no FHR
fetal demise with retained fetus
incomplete AB
presents as thickened and irregular endo and enlarged UT
part of the products of conception are expelled, part is retained within the UT
complete/spontaneous AB
all products of conception are expelled
gestational trophoblastic disease
hydatidiform mole
molar pregnancy
trophoblastic cells produce hCH
bilateral theca lutein cysts typically seen
human chorionic gonodotropin
hCG
produced by the trophoblastic cells of the developing chorionic villi
doubles every 30-48 hrs
peaks at 10th gest. wk
blastocyst
fluid rapidly enters the morula, forming the blastocyst —> implants into the endo 5-7 days after fertilization
morula
a solid mass of cells formed by the cleavage of a fertilized ovum (zygote)
rhombencephalon within embryo
a normal cyst like structure seen within a first trimester embryo
eventually contributes to the 4th ventricle, brain stem, and cerebellum
implantation process
occurs within distal portion of fallopian tube
cells of zygote multiply–>form a cluster of cells (morula)–>fluid fills the morula–>forming a blastocyst–>implants into the endometrium
