Test2:Review Flashcards
What are the three types of holoprosencephaly and which is the most serious?
alobar-most serious
semilobar
lobar
What is the cavity in which the fetus exists?
amniotic cavity
What are the lab tests that indicate pregnancy?
hCG test
Where is the 1st site of red blood cell formation that will nourish the embryo?
primary yolk sac
What is the difference between menstrual and embryonic age?
menstrual age(gestational age)-calculated from the 1st day of the last normal menstrual period
embryonic age(conceptual age)-calculated from when conception occurs
What are monochorionic, monoamniotic, dichorionic, and diamniotic?
monochorionic-one chorionic sac, one yolk sac
monoamniotic-one amniotic sac, one yolk sac
dichorionic-two chorionic sacs
diamniotic-two amniotic sacs
What is decidua capsularis? (understand ring around pregnancy)
villi covering developing embryo
Interface between decidua capsularis and echogenic, highly vascularized decidua on opposite wall of endometrial cavity forms double decidual sac sign
When will hCG levels plateau?
8 wks
When do the chorion and amnion fuse?
16 wks
When should you see the first heartbeat?
5 1/2-6wks
MSD-what size indicates a problem when you can’t see the yolk sac?
> 8mm
How do we measure MSD?
length(mm)+width(mm)+height(mm)/3=MSD
What is the first structure visualized in the gestation sac?
secondary yolk sac
What is the normal size of the yolk sac?
normal diameter should not exceed 6mm
When should we see the abdominal contents back in the fetus?
descends into fetal abdomen at about 11th wk
What is the normal cystic are in the head?
choroid plexus cyst-should be gone by 25wks
What should a normal gestational sac look like?
shape-round or oval
position-fundal or middle portion of uterus; a center position relative to endometrium (double decidual sac or intradecidua finding)
contour-smooth
wall(trophoblastic reaction)-echogenic
internal landmarks-yolk sac present when gestational sac is >12mm; embryo present when gestational sac in >18mm
What does the corpus luteum secrete?
estrogen and progesterone
What are all the different stages follicle to implantation?
mature ovum-released at day 14
fertilization-occurs 1-2 days after conception
morula-16 cell (zygote forms 16 cell morula)
blastocyst-further cell proliferation brings the morula to this stage, enters uterus 4-5 days after ovulation
implantation-completed within 12 days post fertilization
time of implantaion until end of 10th wk-embryo
after 10wks-fetus
1800 m/u hCG
should see a heartbeat (normal gestational sac can be seen)
What are the differnt cavities?
amniotic cavity-cavity in which the fetus exists
amnion(amniotic membrane)-separates the amniotic and chorionic cavities
chorionic cavity-surrounds the amniotic cavity and contains the yolk sac
chorion-outermost extraembryonic membrane
what side is the conceptus on?
fetal/embryonic side
decidua basalis-portion on the myometrial or burrowing side of the conceptus
how quickly will the gestational sac grow?
gestational sac grows at a rate of 1mm/day
measure CRL up to 12wks, then how is the baby measured?
individual parts
what do hCG levels do everyday?
they double
what is an ectopic pregnancy, where are the potential sites, and what is the most common location?
ectopic-pregnancy located outside the uterus
potential sites: isthmic-top of uterus(interstitial portion-most serious-massive hemorrhage or death)
tubal-within fallopian tubes(most common-approx 95% of cases)
ovarian-within ovary
peritoneal-abdominal
cervical-results in full hysterectomy
what is an ovum without an embryo?
anembryonic pregnancy or blighted ovum
what are gastrochisis and omphalocele?
abdominal contents are outside of baby (herniation of bowel-normally goes back approx 11th wk)
gastrochisis-no membrane, surgery is performed right after birth and abdominal contents are placed back inside body
omphalocele-membrane, associated with genetic abnormalities (Tri 13 and 18)
what is acrania?
partial or complete absence of the cranium (mickey mouse head)
predecessor of anencephaly
AFP unusually high
what is ancephaly?
absence of brain and cranial vault
AFP unusually high
what is cephalocele?
midline herniation, protrusion of the brain from the cranial cavity (herniation of brain and meninges)
Western Hemisphere defect primarily occipital
what is iniencephaly?
rare neural tube defect in which brain tissue protrudes through a fissure in the occiput so that the brain and spinal cord occupy a single cavity (open spinal defect)
what is Dandy-Walker malformation?
6th-7th wk gestation, cystic dilation of 4th ventricle
dysgenesis or agenesis of cerebellar vermis and hydrocephally
what is spina bifida?
occurs when failure of neural tube to close after 6wks gestation
spinal irregularities or bulging within posterior contour of fetal spine and extrusion of the mass from vertebral column
cranial signs-lemon sign(scalloping frontal bones), banana sign(curved appearance of cerebellum)
what is Turner’s syndrome?
nonlethal genetic abnormality in which chromosomal makeup is 45XO instead of normal 46XX or XY
only happens in females
born with no ovaries
fetus detected with cystic hygroma in 2nd and 3rd trimester
fibroids in pregnancy
early-must be identified in reference to the location of the placenta
3rd trimester-identified in reference to the cervix
what is the hemorrhage between the gestational sac and placenta?
subchorionic hemorrhage-most common occurrence of bleeding in 1st trimester
when do corpus luteum cysts regress?
typically regress between 16-18wks
ectopic pregnancy-associated risk factors
rise in incidence of pelvic infections
use of intrauterine contraceptive devices
fallopian tube surgeries
approx 10% of maternal deaths related to ectopic pregnancy
infertility treatments
history of ectopic pregnancy
what is a pseudogestational sac?
decidual reaction with fluid present within the uterus in a patient with an ectopic pregnancy (intrauterine saclike structure found in approx 20% of patients with ectopic)
clinical findings associated with ectopic pregnancy
vaginal bleeding
empty uterus
presence of adnexal mass
positive pregnancy test
does not produce normal hCG levels
typical heart rates
typical heart rate: 120-160bpm
embryonic activity should always be seen by 46 menstrual days or when CRL > 4mm
6wks: rates of 90-115bpm
9wks: rates of 140-160bpm
late 1rst-2nd trimester: approx 140bpm
bradycardia: <90bpm (poor prognosis)
tachycardia: >170bpm, moves to hydrops-plueral fluids, pericardial fluids, and acites develop, then blood transfusion
when can you see the bladder?
10-12wks
what happens to hCG levels in trophoblastic disease?
hCG levels are dramatically elevated, often >100,000 IU/ml
what is a heterotopic pregnancy?
pregnancies outside and inside the uterus
