-
What gonadotropin produced by the anterior pituitary gland initiates the development of follicle within the ovary?
FSH
-
As the dominant follicle develops, what hormone does it secrete?
Estrogen (by theca interna cells of Graafian follicle)
-
What hormone influences final stages of follicles development, & peaks causing ovulation?
LH
-
When does menstrual age begin?
first day of LMP
-
When does fetal age begin?
begins at conception (2 weeks less than menstrual)
-
Alternative names for fetal age?
Conceptual age or Embryologic Age
-
Importance of Menstrual Age?
- schedule procedures
- Interpretation of expanded maternal serum alpha-fetoprotein screen
- plan/guess delivery within 38-42 weeks
- evaluate growth
-
What is the triple-marker?
another name for Maternal alpha-fetoprotein
-
Where/When does fertilization occur?
- 24 to 36 hours after ovulation
- Ampullary portion of fallopian tube
-
What is the outer layer of the ovum?
zona pellucida
-
What is a fertilized egg called?
zygote
-
What are gametes?
Ovum/Sperm
-
What is a morula
mitosis to 16-cells
-
What comprises a blastocyst?
trophoblast cells + inner cell mass
-
When do blastocysts occur?
day 7 after fertilization
-
When will a blastocyst implant in the UT?
7-9 days after fertilization
-
What determines a positive pregnancy?
trophoblast produces hCG
-
When would a trophoblast produce hCG?
GA around 3 weeks (days 20-21)
-
During embryonic development, what are the 3 germ cell layers called of the trilaminar disk?
- Endoderm
- Mesoderm
- Ectoderm
-
What do the endoderm, mesoderm, and ectoderm form?
form into all the major organs
-
What is the first organ to function during embryonic development?
heart (day 36)
-
- 1 endometrium
- 2 uterine endometrium epithelium
- 3 inner cell mass
- 4 trophoblast
- 5 blastocyst cavity
- 6 lumen of uterus
- 7 endometrial stroma with blood vessels and glands
- 8 syncytiotrophoblast
- 9 cytotrophoblast
- 10 inner cell mass (future embryo)
- 11 lumen of uterus
-
How many days does it take the zygote to reach the uterus after fertilization?
3-5 days
-
When would you use the term embryo?
up to 9 weeks
-
When would you use the term fetus?
after 9 weeks
-
When does the primary yolk sac cease to function?
around 23 days
-
Which yolk sac is seen during ultrasound?
the secondary yolk sac
-
What does the secondary yolk sac do?
provides blood/nutrients to developing embryo
-
When does the secondary yolk sac form?
27-28 days after MA
-
What is the approximate measurement of the gestational sac when the secondary yolk sac forms?
3 mm
-
What hormone do trophoblasts produce? Why?
produces hCG to extend the life of the corpus luteum
-
What produces proteolytic enzymes?
trophoblasts
-
What is the function of the proteolytic enzymes?
erode the endometrial mucosa and maternal capillaries
-
Def. the cellular and vascular changes occurring in the endometrium at the time of implantation
Decidual Reaction
-
3 layers of the decidual reaction
- decidual basalis
- decidual casularis
- decidual parietalis (vera)
-
Define decidual basalis
where the embryo is implanted into the endometrium (maternal portion of the placenta)
-
Define decidual casularis
thin portion of endometrium that covers the gestational sac
-
Define decidual parietalis (vera)
remaining endometrium unoccupied by the implantation that surrounds the rest of the uterine cavity (besides the implantation site)
-
- 1 chorion laeve
- 2 decidual capsularis
- 3 amniotic cavity
- 4 chorionic cavity
- 5 decidual parietalis
- 6 decidual basalis
- 7 yolk sac
-
- 1 decidual parietalis (vera)
- 2 decidual basalis
- 3 decidual capsularis
-
What will the embryo appear as on week 5 sonographically?
grain of rice
-
What 2 things develop during week 5?
- neurulation
- 2 cardiac tubes
-
When is the embryonic period?
week 6-10
-
What is the most critical time of embryonic development when all the internal and external structures are present and congenital malformations can originate?
Embryonic Period
-
What has developed at the end of week 6?
- brain has 3 segments
- primitive gut has formed
-
What is the sonographic appearance of an embryo that is 8 weeks old?
"peanut" shaped
-
What has developed at week 8?
- heart has adult form
- midgut herniates
- metanephros (primitive kidneys) ascend from pelvis
-
What has developed at 10 weeks?
- major organ systems established
- embryo (maybe fetus) demonstrates human features
-
When will the amniotic cavity fuse with the chorion?
12-17 weeks after last menstrual period
-
What has developed by week 11?
- primitive kidneys reach adult position
- limbs have fingers and toes
- head (large) is disportionate to body
-
What happens at week 12?
midgut retracts into abdomen
-
small GS within an echogenic endometrium with focal thickening at implantation site characterizes what?
Intradecidual sign
-
When can hCG be detected?
3 weeks after LMP
-
What is a Qualitative hCG?
pregnant (yes or no)
-
What is a Quantitative hCG?
how much Glycoprotein is in the blood (suggests age)
-
What does hCG stand for?
Human Chorionic Gonadotropin
-
Def. refers to the level at which a gestational sac should be visible with regards to hCG
discriminatory level
-
What is the discriminatory level for a TV exam?
1500 mIU/ml
-
What is the discriminatory level for a TA exam?
6500 mIU/ml
-
The symptoms below are associated with what?
incorrect dates
gestational trophoblastic disease (molar pregnancy)
multiple gestations
high hCG levels
-
The symptoms below are associated with what?
incorrect dates
ectopic pregnancy
embryonic demise
low hCG
-
Describe the normal sonographic gestational sac appearance
- located within the fundus or midportion of the UT
- small, round/ovoid, anechoic, fluid-filled
- enclosed by hyperechoic walls
-
What is the first structure seen within the gestational sac?
yolk sac
-
Where does the yolk sac lie?
lies between the amniotic and chorionic cavities
-
For TA exams, what MSD measurement of the gestational sac will the yolk sac be visible? (both early and always)
-
For TV exams, what MSD measurement of the gestational sac will the yolk sac be visible?
8 mm
-
What is the normal diameter of the yolk sac at 5-10 weeks?
5.6mm
-
What are the functions of the yolk sac?
- provides nutrients to embryo
- hematopoesis
- development of the embryonic endoderm (forms primitive gut)
-
-
When does the double-bleb sign occur?
5th-7th week
-
What is the double-bleb sign?
it's when the amniotic and yolk sac approximately the same size
-
-
What the 2 fetal membranes?
-
What becomes the covering of the umbilical cord?
amnion
-
When does the amnion fuse with the chorion?
between 12-16 weeks
-
The Amnion is not vascular and develops from what?
endoderm
-
This structure surrounds the gestational sac and merges with the edge of the placenta.
Chorion
-
Which gender provides the structures below?
inner cell membrane
embryo
amnion
yolk sac
females
-
Which gender provides the structures below?
trophoblastic tissue
placenta
hCG
gestational sac (chorion)
males
-
5 functions of the amniotic cavity
- symmetrical growth
- Prevents adhesions in the fetal membrane
- Cushions embryo
- maintain temperature
- Allow movement = muscle tone
-
What areas produce amniotic fluid?
- chorion frondosum
- chorionic membrane
- amniotic membrane
- skin
- urinary tract
-
What is primarily responsible for amniotic fluid production?
urinary tract
-
In the 2nd/3rd trimester amniotic fluid is regulated by what?
fetal urination, swallowing, and fluid exchanges in lungs, membranes, and cord
-
What is the sonographic appearance of amniotic fluid?
anechoic with or without free-floating particles
-
Def. not enough amniotic fluid
oligohydramnios
-
Def. too much amniotic fluid
polyhydromnios
-
What is associated with oligohydramnios?
renal abnormalities
-
What is associated with polyhydromnios?
maternal complications, trisomy, GI obstruction
-
What is the sonographic appearance of chorionic fluid?
more echogenic than amniotic fluid
-
Def. Embryonic tissue lining the exterior of the gestational sac
Chorionic cavity
-
What is the purpose of the chorionic cavity?
to invade the decidua and establish nutrition for the embryo
-
Define Chorionic Villi
finger-like projections that project outward from the walls of the blastocyst into the decidua
-
Define chorionic frondosum
portion of the chorion located at the implantation site which later contributes to the formation of the placenta
-
Define chorionic laeve
thinly stretched chorion frondosum that didn't proliferate
-
A heart rate will be visible on a TV exam when the CRL measures what?
4-5mm
-
What is the normal heart rate at 6 weeks?
90 bpm
-
What is the normal heart rate at 9 weeks?
170 bpm
-
What is the normal heart rate between 10 and 24 weeks?
140 bpm
-
When does the umbilical cord form?
end of 6th week
-
What is contained in the umbilical cord?
- 2 arteries
- 1 vein
- Allantois
- Yolk stalk
-
What umbilical structure is associated with bladder development?
allantois
-
What umbilical structure connects the primitive gut to the yolk sac?
yolk stalk
-
-
-
Def. gelatinous substance within the umbilical cord
Wharton's Jelly
-
How is the gestational sac measured?
H+W+L/3=MSD
-
Where do you measure the gestational sac?
at the fluid-tissue interface
-
How accurate is the gestational sac measurement for determing embryonic age?
accurate to within one week
-
When would you stop measuring the gestational sac for embryonic age?
when the embryo is visible
-
Which transducer is most accurate for measuring structures during early OB?
high frequency transvaginal probes
-
A gestational sac measuring MSD = 2mm corresponds to what age?
4-4.5 weeks
-
A gestational sac measuring MSD = 5mm corresponds to what age?
5 weeks
-
At what age will the yolk sac appear?
5.5 weeks
-
At what age will the embryo and yolk sac be visible?
6 weeks
-
What is the most accurate of all fetal measurements?
crown rump length
-
How many CRL should be taken?
3 for accuracy and averaging
-
When the fetal pole is visible how quickly does it grow?
1-2 mm per day
-
How is gestational age calculated from CRL?
CRL (mm) + 42 = GA (days)
-
When are CRL no longer necessary?
after the 12th week
-
Why are CRL measurements less accurate after the 12th week?
due to curling
-
Prosencephalon AKA
Forebrain
-
Mesencephalon AKA
Midbrain
-
Rhombencephalon AKA
Hindbrain
-
-
When do the lateral ventricles appear?
9-11 weeks
-
When does the choriod plexus appear?
13 weeks
-
Sonographic appearance of lateral ventricles?
anechoic
-
Sonographic appearance of choroid plexus?
homogeneous, echogenic
-
Choroid Plexus / Lateral Ventricles
-
Def. failure of the fetal gut to return after it herniates
omphalocele
-
Def. Absence of cranial vault/cerebral hemispheres
Anencephaly
-
Def. Lucency at the back of
head/neck
Nuchal Translucency
-
Def. termination of the pregnancy prior to 20 weeks
abortion
-
Spontaneous Abortion will occur approximately _____ weeks after embryonic demise.
1-3
-
What percentage of pregnancies end in spontaneous abortion?
12%
-
75% of spontaneous abortions occur before _____ weeks.
16
-
What are some causes of Spontaneous Abortion?
unknown, endocrine factors, failure or corpus luteum, interruption of embryonic development, chromosomal anomalies
-
Spontaneous Abortion begins with ________ into the decidual basalis, followed by _______ and ________ around the implantation site causing the embryo to die.
- hemorrhage
- inflammation
- necrosis
-
What will the uterus and cervix do after a spontaneous abortion?
uterus contracts, cervix dilates, and pregnancy is expelled
-
What happens during a complete abortion?
- Evacuation of ALL products of conception
- Rapid decline in hCG levels
- Vaginal bleeding with clots and tissue
- Very painful cramping
- Pregnancy symptoms disappear
- Cessation of pain and bleeding after conceptus is passed
- Sonographic appearance- thin endometrium, empty uterus
-
What happens during an incomplete abortion?
- Partial evacuation of products of conception
- Slow fall or plateau of hCG levels
- Moderate cramping
- Persistent bleeding
- Sonographic appearance- presence of complex echoes in endometrial cavity, retained products of conception
-
-
What happens during a missed abortion?
- Presence of embryo/GS in uterus but no cardiac activity
- hCG levels less than expected for dates
- Loss of pregnancy symptoms
- Brownish bleeding ordischarge without heavy bleeding or cramping
- Sonographic appearance- no cardiac motion, no fetal motion, size < dates, hypoechoic embryo
-
-
Def. Condition in which the pregnancy appears normal but clinical signs such a bleeding or cramping suggest pregnancy is in jeopardy
Threatened abortion
-
What happens during an inevitable abortion?
- SAB is imminent when any of 2 or more of the following clinical signs are noted:
- Moderate effacement of the cervix (shortening)
- Cervical dilatation > 3cm
- Rupture of membranes (little or no AFV)
- Bleeding for more than 7 days
- Persistent cramping
- Sonographic appearance- GS seen in the cervix or LUS, cervical dilatation
-
Def. gestational sac seen in uterus but embryo failed to develop or died at a stage before it was visible
anembryonic pregnancy
-
What was an anembryonic pregnancy formerly called?
blighted ovum
-
What is the sonographic appearance of an anembryonic pregnancy?
large gestational sac with no amnion, yolk sac, embryo
-
What risks are associated with a large yolk sac?
increase risk for spontaneous abortion and embryonic demise
-
What is the max diameter of the yolk sac at 10 weeks gestation age?
5-6 mm
-
What risks are associated with abnormally shaped or calcified yolk sacs?
embryonic demise
-
A CRL of 5-9 mm with a heart rate of < 100 BPM or a CRL of 10-15 mm with a HR of < 115 BPM indicates
Embryonic Bradycardia
-
What is the most common reason for bleeding during the first trimester?
Subchorionic Hemorrhage
-
Def. an accumulation of blood beneath the chorion
Subchorionic hemorrhage
-
What is the sonographic appearance of an acute chorionic hemorrhage?
- hyperechoic to isoechoic relative to placenta
- 1-2 weeks sonolucent
-
What is the most important criteria for subchorionic hemorrhage?
- size of the bleed
- should decrease with follow-up scans
-
-
-
Describe an early pregnancy failure.
- Pregnancy shows sonographic evidence of cessation of growth & development & clinical findings are supportive
- Examples
- Large empty GS
- GS & Yolk sac only
- No CA & smaller than normal or appropriately sized embryo
- Remnants of a sac
-
What is the name for a surgical abortion?
suction dilation and curettage (D&C)
-
What pills cause a medical bortionl?
- mifepristone (600mg)
- 2 days later misoprostol (400 µg)
-
91% of expectant miscarriages occur after ____ days.
9
-
What is the leading cause of pregnancy related deaths during the first trimester?
ectopic pregnancy
-
Ectopic pregnancy is the cause of ____% of all pregnancy related deaths.
15
-
What has caused ectopic pregnancies to increase of the past 10 years?
-
What are the symptoms of ectopic pregnancy?
- + pregnancy test and empty uterus
- adnexal mass
- vaginal bleeding
- lower abdominal pain
- cramping on one side of the pelvis
- sharp, stabbing pain in the pelvis, abdomen, or even shoulder or neck
- dizziness
- lightheadedness
-
What are the risk factors for ectopic pregnancy?
- Pelvic inflammatory disease (PID) -- 6 to 10 times higher than in women with no previous history of PID.
- Previous ectopic pregnancy
- Progesterone-bearing
- IUD's -- 16% of pregnancies in women using progesterone containing IUD's were ectopics.
- Tubal ligation
- (sterilization) -- After non-laparoscopic tubal ligation, about 12% of
- pregnancies are ectopic; after laparoscopic tubal coagulation, about 51% of pregnancies are ectopic.
- Previous tubal surgery
- Fertility treatment with ovulation induction or ovarian stimulation
- In vitro fertilization (IVF) -- About 2 to 5% of clinical pregnancies resulting from IVF are ectopic. The figure is higher for women with a history of previous ectopic pregnancy or tubal infertility.
- Some studies have suggested that tubal pregnancies are more likely in African American women.
- Douching
- Smoking
-
What poplulation is at most risk for an ectopic pregnancy?
- Varies patient population & inherent risk factors
- All patients of reproductive age
-
Heterotopic
Ectopic pregnancies
- Coexistent intrauterine & ectopic
- IVF & ovulation induction
- 1 in 2000 pregnancies
-
-
What is the ring of fire sign?
a tubal pregnancy with peripheral hypervascularity surrounding the extrauterine gestational sac
-
What should you demonstrate if there is a live embryo in the adnexa
show cardiac acitivity in M-mode, color, and power dopplar
-
Empty uterus and adnexal mass
hCG >1500 mIU/ml
Free fluid in pelvis
Look for decidual reaction and “ring of fire” around ectopic
-
Sonographic pitfalls “pseudogestational sac”-fluid in the endometrial canal
Mimics normal GS
Look for decidual reaction
-
-
Surgical
Resection of diseased tube
Early diagnosis w/ TV = more conservative
Laporascopy
Definitive diagnosis
Medical
Goal is to find early before rupture
Methotrexate
61-93% success
-
Methotrexate
Cell growth inhibitor
-
Spectrum of pathologies resulting from the excessive proliferation of trophoblastic tissue
Paternal genomes control the proliferation of trophoblastic tissue, maternal genomes control growth of the embryo
GTD is caused from excessive paternal genomes
Complete mole
Partial mole
Invasive mole
Choriocarcinoma
Mole with coexisting normal fetus
Gestational Trophoblastic Disease
-
GTD clinical signs
- Grossly elevated hCG levels >100,000 mIU/ml
- Hyperemesis gravidarum (severe morning sickness)
- Rapid enlargement of the uterus
- Vaginal bleeding
- Theca lutein cysts
- Early onset of preeclampsia (htn, edema, proteinuria)
- Hyperthyroidism
-
Most common form of GTD
1:1500 USA; 1:82
Taiwan
Risk factors include:
< 20 yrs and >40 yrs
Low economic status
Diets deficient in protein and folic acid
Genetics:
1: Duplicated male chromosomes and normal ovum
2: Normal male chromosomes and empty ovum
Complete Molar Pregnancy
-
Haploid
Single set of unpaired chromosomes
-
Hydropic chorionic villi enveloped by hyperplastic atypical trophoblasts
No embryo or fetal tissue is present
Sonographic findings:
Multiple scattered cystic spaces filling a thickened endometrial cavity- “cluster of grapes”
Uterus larger than dates
Enlarged ovaries from theca lutein cysts
Complete molar pregnancy
-
-
2 normal sperm fertilize the same normal ovum
2 types of chorionic villi
Normal
Hydropic swelling (trophoblastic hyperplasia)
Partial mole
-
Pathology
Deformed GS
Growth-restricted fetus with anomalies
Large placental size with cystic spaces
Trophoblastic proliferation not as severe
Symptoms
Less severe than complete
Sonographic appearance is similar to a missed or incomplete abortion
Partial Molar Pregnancy
-
partial mole first trimester
-
Therapy for molar pregnancy
- Uterine evacuation
- Monitor serum hCG-should fall over 10-12 weeks
- Avoid pregnancy for 1 yr.
-
2 conceptions occur as in twinning, but one develops into a mole and the other a normal fetus
Cases have been reported of normal going to term, but itis very risky. Mom has to be monitored closely for hemorrhage, severe HTN, or toxicity
Maternal risks are significant and termination is given as an option; Risk for future molar pregnancy or PTN increases
Mole with coexisting normal fetus
-
2 types of Persistent trophoblastic disease
- Invasive mole
- choriocarcinoma
-
Persistent trophoblastic disease
- PTN can follow normal pregnancy, SAB, ectopic pregnancy, or GTD
- Severe cases of GTD are at the highest risk for PTN
-
AKA Chorioadenoma destruens Most common form of PTN (80-95%)Trophoblastic tissue that penetrates the myometrium and/or adjacent structures. May penetrate the uterine wall and cause uterine rupture and hemoperitoneum Considered a malignant, non-metastatic form of GTDDiffuse echogenic material with cystic spaces filling the endometrial cavity and extending into myometrium (“more mole than uterus”)
Invasive Mole
-
-
very rare1:30,000 pregnancy; 1:40 molar pregnanciesVascular invasion, hemorrhage, and necrosis of the myometrium are commonTumor composed of syncytiotrophoblastic and cytotrophoblastic cellsConsidered the malignant, metastatic form of GTDCan metastasize to the lung, brain, liver, bone, GI tract, or skin
Choriocarcinoma
-
Name Disease:
Elevated hCG
No embryo or fetal tissue present
Enlarged uterus
Mass with complex, marked vascularity
Choriocarcinoma
-
-
Treatment for PTN
- Chemotherapy
- Radiation
- Hysterectomy
- Treatments performed as needed based on severity of disease
-
If abnormality is suspected in 1st trimester follow-up is recommended or genetic testing: by testing what?
- Serum alpha-fetoprotein
- CVS
- Amniocentesis
-
What is the major advantage of screening anomalies in the 1st trimester?
maternal reassurance and/or counseling for parents of structurally abnormal fetuses
-
Def. performed from 15 wksAmniotic fluid is drawn ransabdominally under U/S guidance to avoid fetus, placenta, and umbilical cord
Amniocentesis
-
List the Genetic Testing options
- MSAFP- can detect
- ONTD’s-open neural tube defects
- Trisomy 13, 18, 21
- Abdominal wall defects
- Chorionic Villus Sampling – performed 9-12 weeks gestation
- U/S guidance transcervically or transabdominally
- Trophoblastic cells are obtained and can reveal karyotype, chromosomal abnormalities,
- Termination can be performed earlier if elected
- Amniocentesis – performed from 15 wks
- Amniotic fluid is drawn transabdominally under U/S guidance to avoid fetus, placenta, and umbilical cord
-
What type of US scans are the most accurate for assessment of fetal anatomy
TV and TA sonograms are used for the most accurate assessment of fetal anatomy
-
When do most congenital anomalies occur?
Most originate in embryonic period
-
When are most congenital anomalies diagnosed?
Most anomalies are diagnosed in the 2nd trimester due to fetal immaturity affecting visualization
-
List some congenital anomalies
- CNS
- Fetal face
- Fetal neck
- CV system
- GI tract
- Genitourinary System
- MS system
-
Def. exaggerated, hyperextension of the neck, open spinal defects, occipital encephalocele
Iniencephaly
-
Def. protrusion of the brain through a bony defect in the skull
Encephalocele
-
Def. absence of the brain and cranial vault, base of skull and face are present along with some brain tissue
Anencephaly
-
Def. partial or complete absence of the cranium, bony structures absent
Acrania
-
Def. lack of closure of the spinal column, bulging of spine or meninges into a sac; prognosis depends on severity
Spina Bifida
-
Def. cystic dilatation of the 4th ventricle and abnormal configuration of the cerebellum
Dandy-Walker malformation
-
Def. 3 levels of severity, absence of brain tissue in varying degrees; no cerebral hemispheres or ventricles
Holoprosencephaly
-
Def. hydrocephaly, dilatation of the ventricles without enlargement of the cranium; increased amount of CSF
Ventriculomegaly
-
Def. herniation of the abdominal contents into the umbilical cord; often associated with other congenital anomalies
Omphalocele
-
Def. open defect in the anterior abdominal wall; organs are not covered by a membrane, they are seen “floating” in the amniotic fluid; not associated with other congenital anomalies
Gastroschisis
-
Def. One of the most common abnormalities seen in the 1st trimesterSingle or multiple cystic areas, of lymphatic origin, within the soft tissue surrounding the neckAssociated with chromosomal abnormalities such as Turner’s and Down syndromes
Cystic Hygroma
|
|