ashlyn copy_NEED TO KNOW

identify: embryo, secondary yolk sac, and amnion in this photo!

identify decidua in this photo!

What contributes to the maternal portions of the placenta

Decidua Basalis

What is the normal number of chromosomes for Ova, sperm, and embryo

Ova = 23X

Sperm= 23X or 23Y

Embryo = 46XX or 46XY

The order of which structures appear on ultrasound (yolk sac, gest sac, embryo)

• Gestational sac: 4-5 weeks

• Yolk sac: 5-6 weeks

• Embryo (fetal pole) with heartbeat: 6 weeks

Qualitative and Quantitative HCG levels:

• which one is more accurate for determining gestational age

• know the difference!

Qualitative: Pregnancy test, simple positive or negative

Quantitative: Measures amount of HCG in maternal blood; more diagnostic info; much more accurate

what is shown?

anembryonic pregnancy aka blighted ovum

blighted ovum on US?

• empty gestational sac

• may see double ring BUT NO EMBRYO OR YOLK SAC

• may see debris in sac that looks similar to yolk sac

• will see trophoblastic flow (ring of fire)

• sac grows more slowly than expected

Know about the anembryonic pregnancy aka blighted ovum:

• pregnancy failed to occur prior to development of an identifiable embryo/ embryonic tissue has been resorbed after early embryo demise

• caused by sperm that fertilizes an ovum that is abnormal

• there is no/ never was an actual baby

What size would the empty gestational sac be diagnose a blighted ovum?

Empty gestational sac with MSD > 25mm

Which anomaly is most commonly associated with cystic hygroma

most predominant by mid pregnancy= Turner syndrome

Also associated with autosomal trisomy’s and trisomy 21.

1. What does molar pregnancy look like?

2. difference between partial and complete?

3. definition of complete molar pregnancy?

They appear as complex intrauterine mass early on.

Complete molar -

• no maternal chromosomes= proliferation of swollen chorionic villi and the absence of identifiable embryonic structures

• stays as empty gest sac.

Partial molar -

• One maternal and two paternal sets of chromosomes, leading to development of an abnormal embryo and placenta

• becomes abnormal fetus

What are the findings of an embryonic demise on ultrasound

Empty amnion sign

Absence of cardiac activity when CRL >5mm

Know the definition of missed abortion

Embryo/fetus has died but gestational sac and contents remain within the uterus

Know the definition of inevitable abortion

Conceptus located within uterus but cervix is open and gestational sac is in the process of exiting the uterine cavity. Embryo may or may not be alive

Know the definition of incomplete abortion

Embryo has died and part of the products of conception have been expelled but some parts still remain within the uterus

Know the definition of complete abortion

All of the products of conception leave the body

Know what a subchorionic hemorrhage looks like on an ultrasound image

Fluid collection between gestational sac and uterine wall

Fetal heart rate rule, what’s a normal level, what is low, what is high

Normal is 120-180 bpm

Below 100-110 is bad

Above 160-180 is bad

DO NOT use anything but M-Mode on a fetus 12 weeks or less; DO NOT use PW or Color Doppler

When is fertilization possible?

24-48 hours after ovulation

Where does fertilization almost always occur in?

Ampulla of the fallopian tube

What does a trophoblast secrete?

hCG

What forms the point of exchange of maternal and fetal blood components

Chorionic villi

What type of yolk sac can be seen on ultrasound

Secondary

What is the first embryonic structure visible on ultrasound?

Secondary yolk sac

Most common type of gestational trophoblastic neoplasia

Hydatidiform Mole