Ch 49 Obstetrics Sonography, Ch.49 First Trimester
_____system is the first organ to develop rapidly
Cardiovascular
_____is the first day of the pregnancy
Conception
What happens on day 54 of pregnancy?
Digital rays are distinct
_____ age dates the pregnancy with the first day of the LMP as the beginning of gestation
Gestational
What happens on day 36 of pregnancy?
Heart beat begins
__________________ hCG is sign of down syndrome.
Increased
IUP stands for
Intrauterine Pregnancy
What happens in week 6 of pregnancy?
Neuropores close and neural tubes form
PAPP-A stands for
Pregnancy associated plasma protein A
What happens in week 5 of pregnancy?
Prominent neural folds/grooves
____________________ secrete hCG
Trophoblastic cells
What happens on day 41 of pregnancy?
Upper and lower limb buds are present
What happens on day 52 of pregnancy?
Upper lip is formed
Within the conceptus, the inner cell mass matures into the ____,___,&_____
bilaminar embryonic disk, the future embryo, and the primary yolk sac.
During implantation, proteolytic enzymes produced by the trophoblasts erode endometrial mucosa and maternal capillaries develop a primitive_______ between mother and conceptus
blood exchange network
What happens on day 48 of pregnancy?
cerebral vesicles are distinct
Embryologists state time in ________ age
conceptual
the follicle that released the mature ovum hemorrhages and collapses to form the_____
corpus luteum
What happens on day 42 of pregnancy?
crown-rump length is 4.0 mm
Demise means
death
hCG causes the uterine endometrium to convert to _____________.
decidua
The echogenic ring around the gestational sac can be divided embryologically into several components. The portion on the myometrial or burrowing side of the conceptus is known as the _______
decidua basalis.
Villi covering the rest of the developing embryo are referred to as the _______
decidua capsularis
Villi normally______ over the area of the sac where implantation does not occur
degenerate
DNA stands for
deoxyribonucleic acid
A Reliable sign of a viable gestation is called
double decidual sac sign
After 7 weeks hCG should be ______________ every 3.5 days.
doubling
When the hCG level is elevated and an intrauterine gestational sac is not seen an _____ should be considered
ectopic pregnancy
1st 9 weeks the conceptus is called
embryo
In the first 9 weeks the conceptus is called an____
embryo
conceptual age is also known as ______age
embryologic
Conceptual age is also known as
embryologic age
hCG levels ____before spontaneous expulsion of nonviable gestation
fall
Fertilization occurs in
fallopian tube
The last 2 weeks of the first trimester (11 and 12) constitute the beginning of the ____period
fetal
After 9 weeks embryo is called a
fetus
After the first 9 weeks the embryo is called the ____
fetus
Sonographers need to obtain quantitative hCG levels whenever possible before_____ obstetric examinations are performed
first-trimester
Clinicians and sonographers use _____age
gestational
When implantation is complete, the trophoblast has formed primary villi, which initially encircle the early _____
gestational sac.
hCG stands for
human chorionic gonadotropin
An intimate relationship between the sonographic findings and quantitative serum____________________ levels normally exist during early pregnancy
human chorionic gonadotropin (hCG)
12 days after conception is:
implantation process (zygote)
PAPP-A _____________ during gestation.
increases
Amniotic means
inner
Abnormal pregnancies demonstrate a____ hCG level relative to gestational sac development
low
Ectopic pregnancies have ______________ hcG.
lower
Trisomy 21 pregnancies have ___________ PAPP-A levels
lower
Adnexa is
made up of fallopian tubes and ovaries
gestational age is also known as ____ age
menstrual
Gestation age is also known as
menstrual age
If the hCG isn't rising could result in _________________ in the 1st trimester.
miscarriage
Zygote undergoes rapid cell division to form a ___________.
morula
What happens on day 50 of pregnancy?
oral and nasal cavities are confruent
Chorionic means
outer
What happens on day 46 of pregnancy?
paddle shaped hand plates are present
At 8 weeks hCG levels ______________ and __________________.
plateau, decrease
Corpus Luteum secretes_____&_____
progesterone and estrogen
The _____ is seen sonographically throughout the first trimester
secondary yolk sac
What type of transducer do you use in the first trimester?
transvaginal
See the____before the beating embryonic heart
yolk sac
What are the Goals for sonography in the first trimester?
- Visualization and localization of the gestational sac - Identification of embryonic demise or living embryonic gestation - Identification of embryos that are still alive but at increased risk for embryonic or fetal demise - Determination of the number of embryos and the chorionicity and amnionicity in multifetal pregnancies - Estimation if the duration or menstrual age of the pregnancy - Early diagnosis of fetal anomalies including identification of embryos that are more likely to be abnormal based on secondary criteria
Normal sonographic features of a gestational sac are? - _____ or ____-shape - Fundal position or an eccentrically placed position in the middle portion of the____ - _____contours - Decidual wall thickness greater than ____ - A yolk sac can be seen with a mean sac diameter (MSD) greater than____ - Gestational sac size grows at a predictable rate of ____ in early pregnancy
-Round, oval - uterus -Smooth -3mm - 18mm -1 mm/day
In a intrauterine pregnancy ultrasound image, • the Sonolucent center represents the _____ cavity • Circumferential echogenic rim surrounding the gestational sac represents _____ associated with decidual reaction
-chorionic -trophoblastic tissue
The interface between the ______and the echogenic highly vascularized_______forms the double decidual sac sign
-decidua capsularis - endometrium
After 8 weeks the hCG levels plateau and ____ while the gestational sac continues to ___
-decline -grow
All embryonic dates reflect _____age rather than _____age
-menstrual -embryologic
Fertilized ovum, now referred to as a ____, undergoes rapid cellular division to form the ____
-zygote -morula
What are your hCG levels for week 3?
0-5
fertilization occurs within _to ___days after ovulation.
1 2
Fertilization occurs how many days after ovulation?
1-2 days
What are your hCG levels for week 6?
1080-56,500
During a 28-day menstrual cycle, a mature ovum is typically released at day ___.
14
Ovulation is the ________ day of a normal 28 day cycle
14th
What are your hCG levels for week 5?
18-7340
Normal gestational sac is visible when the hCG is ___________________.
1800
A normal gestational sac can be consistently demonstrated when the hCG level is _______(Second International Standard) or greater when using TA
1800mIU/ml
Conceptual age is the
1st day of pregnancy (conception)
Gestation age is the :
1st day of the last menstrual cycle
The intrauterine pregnancy (IUP) Appears as a____ sac with an echogenic ring having a sonolucent center
1‐2mm
the gestational age would add __ weeks onto the conceptual age.
2
At approximately __ days of menstrual age, the primary yolk sac is pinched off by the extraembryonic coelom, forming the secondary yolk sac.
23
What are your hCG levels for week 10-12?
25,700-288,000
The gestational sac is approximately____ mean sac diameter (MSD)
25mm
The Crown Rump Length measures ____by the end of the 10th week
30mm
The blastocyst typically enters the uterus __to __days after fertilization.
4 5
Secondary yolk sac is routinely seen between_____ weeks
5 - 5 ½
How many weeks does the initial heartbeat happen?
5 1/2 to 6 wks
Initial heart beat between____and___weeks
5 ½ 6
Between_____ weeks of gestation the amniotic cavity and membrane, chorionic cavity, yolk sac, and embryo should be seen
5 ½ and 6
What are your hCG levels for week 4?
5-426
What frequency is used with transvaginal?
5-8 MHz
The hCG level is significantly reduced by EV and may be as low as _____
500 mIU/ml
The intrauterine pregnancy (IUP) can be visualized in the___ week of embryonic development
5th
Embryonic phase is between week ___-__
6‐10
What are your hCG levels for week 7-8?
7650-229,000
Implantation occurs __-___days after ovulation
7‐9
Gestational sac size and hCG levels increase proportionately until___menstrual weeks
8
PAPP-A analysis is strongest at how many weeks?
9 to 11 weeks
What is trisomy 21?
A form of down syndrome (common)