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Flashcards in First trimester complications Deck (55)
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1

when should the gestation sac be present

1800 mIU/ml TA
1000 mIU/mL TV

2

gestational sac diameter

l+ W+ H /3 = #

3

CRL

Most accurate (+/- .5 wks) (3 days)
used b/t 6- 12 wks
longest length excluding legs

4

what does crown-rump length plus 6 equal

gestational weeks

5

normal Gestational Sac

A normal GS grows 1.1mm/day from 5 to 8 weeks

6

what is the GS meaurement

Reliable indicator of gestational age prior to identification of CRL

7

when is the GS used to determine GA

Used to determine GA up to 6 weeks then MSD is primarily used to correlate GS size to CRL

8

Crown rump length

Embryo grows at a rate of 1 mm/day in the 1st trimester
Curled position
GA from 5.5 weeks +
Measurement from the top of head to the lower edge of torso
reflects embryonic growth

Highly accurate - Error of +/- 3 to 5 days

CRL used until 12 to 13 weeks

9

when should embryo be seen

TA = 25mm MSD
EV = 16mm MSD

10

what percent of clinically recognized pregnancies are spontaneously miscarried

15%`
; loss rate may be even higher for early, clinically unrecognized pregnancies.

11

most common presentation for complications

Most common presentation for complications is vaginal spotting or frank bleeding, occurring in nearly 25% of patients during early stage of pregnancy.

12

implantation bleed

Appears post implantation (21days LMP)
Visible at 6-10 weeks
Sonographically may appear as a sonolucent space outside the gestational sac
Patient may be asymptomatic or present with painless spotting

13

subchorionic hemorrhage

Most common occurrence of bleeding in first trimester is from subchorionic hemorrhage.
Low-pressure bleeds result from process of implantation of fertilized ovum into endometrial cavity and myometrial wall.
Hemorrhage found between myometrium and margins of gestational sac; may or may not be associated with placenta

14

clinical findings of subchorionic hemorrhage

bleeding, spotting or uterine cramping; if hemorrhage becomes large enough, can lead to spontaneous abortion

15

findings can distinguish subchorionic hemorrhage from what

abruption placentae

16

subchorionic hemorrhage appearance

Crescent-shaped sonolucent fluid collection between the gestational sac and the uterine wall

17

if subchorionic hemorrhage is symptomatic (bleeding) increased chance of

miscarriage,
preeclampsia,
placental abnormalities,
preterm delivery

18

Size date discrepancy

Unsure LMP (incorrect dates)
Presence of
Fibroids
Scarring
Obesity
Multiple gestation
Molar pregnancy
Pregnancy failure

19

diagnosis of a true GS may be made only in the presence of

yolk sac or embryo

20

without findings of intrauterine pregnancy, an intrauterine fluid collection could represent

pseudogestational sac associated with ectopic pregnancy

21

embryonic heart rates

5 - 6 weeks - 100 BPM
6+ weeks - 120 to 160 BPM

22

findings diagnostic of pregnancy failure

CRL of >7mm and no heartbeat

Mean sac diameter of >25mm and no embryo

Absence of embryo with heartbeat of >2wk after a scan that showed gestational sac without a yolk sac
``
Absence of embryo with heartbeat >11 days after a scan that showed a gestational sac with a yolk sac

23

Abortion

Spontaneous or induced termination of an early pregnancy and expulsion of fetal and placental tissues.

24

Anembryonic pregnancy (Blighted ovum)

Pregnancy that has failed prior to the development of an identifiable embryo or in which embryonic tissue has been resorbed after early embryo demise

25

Incomplete abortion

Spontaneous abortion in which some products of conception remain in the uterus

26

Inevitable abortion

Failed early pregnancy that is in the process of being expelled from the uterus

27

Miscarriage

Spontaneous failure and expulsion of an early pregnancy

28

Missed abortion

Early failed pregnancy that remains in the uterus

29

gestational trophoblastic disease

Abnormal trophoblastic proliferation
Abnormal chromosome number
46 XX or 46 XY
69 XXX, 69 XXY, 69 XYY…..

30

Ectopic pregnancy

Implantation of a fertilized ovum in any area outside of the endometrial cavity

31

Associated risk factors if ectopic pregnancy

Rise in incidence of pelvic infections
Use of intrauterine contraceptive devices (IUCDs)
Fallopian tube surgeries
Infertility treatments
History of ectopic pregnancy

32

clinical presentation of ectopic pregnancy (most common)`

Vaginal bleeding
Pain
Palpable adnexal mass

33

other clinical presentations of ectopic pregnancy

non
amenorrhea
hypotension
shoulder pain
rebound tenderness
guarding
hypovolemic shock

34

ectopic b-HCG levels

Lower than normal value
Nonvisulaization of pregnancy at discriminatory level
1500 – 2500 mIU/mL

35

sites of ectopic pregnancy

fallopian tube -95%
ampulla (70%)
isthmus (12%)
fimbria (11%)
Intramyometrial (Interstitial) – 2-4%
nual, Cervical, Intramural, Ovarian, Abdominal – 1%

36

most important finding when scanning for ectopic pregnancy is to determine

If normal intrauterine gestation (reducing probability of ectopic pregnancy)
If uterine cavity empty and adnexal mass present
As many as 20% of patients with ectopic pregnancy demonstrate intrauterine saclike structure known as pseudogestational sac.

37

Pseudogestational sac

Normal appearance
Thickened endometrium to 8 mm
Pseudosac vs normal Double decidual sac sign (DDSS)

38

Sonographic findings of ectopic pregnancy

Identification of extrauterine sac within adnexa one of most frequent findings of ectopic pregnancy
Extrauterine gestational sacs often demonstrate thickened echogenic ring, separate from ovary, which represents trophoblastic tissue or chorionic villi and possibility that embryo or yolk sac will be seen.

39

Color dopplere ectopic pregancy

Ring of fire sign
Due to increased flow surrounding the ectopic
Spectral Doppler shows low flow
Corpus luteal flow has similar characteristics

40

what is the most life-threatening ectopic gestation

Interstitial pregnancy, or cornual pregnancy
Location of this ectopic pregnancy is in segment of fallopian tube that enters uterus.

41

Cervical ectopic pregnancy

Hourglass shaped sac in cervix
Pending abortion vs. ectopic
Sliding sac sign (sliding of the gestational sac within the cervix when the transducer is gently pressed against the cervix)

42

Ovarian ectopic pregnancy

Normal tube
Gestational sac on ovary
Ovary and gestational sac connected by the ovarian ligament
Placental tissue mixed with ovarian cortex

43

Abdominal ectopic pregnancy

Fetus outside of the uterus
Failure to image uterine wall between fetus and urinary bladder
Close proximity to maternal anterior abdominal wall
Localization of placenta outside of the uterus

44

Heterotopic pregnancy

Ectopic coexisting with intrauterine (IUP) pregnancy
Incidence
1:30,000 natural pregnancies
1-3% with ovulation induction
IUP may go to term when ectopic has been resolved

45

Acute rupture

Formation of a complex mass
Large adnexal mass
Free fluid
Hematosalpinx
Hemoperitoneum
Morison’s pouch
Pelvic cul-de-sacs

46

Alternate modalities ectopic pregnancy

Defines ectopic
Maturity of present blood
Gold standard

47

treatment ectopic pregnancy

Expectant
Spontaneous regression
Tubal abortion
Methotrexate (MTX)
Surgery

48

fetal aneuploidy

Chromosomally abnormal

49

risk of fetal aneuploidy determined by

Maternal Serum biochemistry levels
Nuchal lucency measurements
Ductus venosus Doppler

50

when is NT measurement taken

45-84mm

51

what does NT meaurement do

Single most powerful marker available to differentiate euploid pregnancies from Down syndrome

52

Nuchal lucency meaurements

“a value of less than ~2.2-2.8 mm in thickness is not associated with increased risk, however it is maternal age dependent and needs to be matched to exact gestational age and  (CRL)”

53

Anembryonic pregnancy (Blighted ovum)

Gestational sac in which embryo fails to develop at an early stage that it is unseeable by ultrasound

54

what occurs in blighted ovum

trophoblast tissue continues to grow, gestational sac continues to grow, BHCG levels continue to increase (but not at expected rates)

55

what is the findings associated with blighted ovum

Large, empty gestational sac with no yolk sac, amnion or embryo