Normal Gestation Flashcards
Tiny cystic structure implanted within the echogenic decidua
Intradecidual sign
Normal sac has an echogenic border greater than ____ mm thick, which represents chorioresidual reaction
2mm
Normal gestational sac is visualized by transabdominal approach by what week
5 weeks
Evident in about 85% of normal pregnancies. It is produced by visualization of 3 layers if decidua in early pregnancy
Double decidual sac sign
Refers to endometrium of pregnant uterus
Decidua
Lines the endometrial cavity
Decidua vera
Covers the gestational sac
Decidua capsularis
Contributes to the formation of placenta at the site of implantation
Decidua basalis
Growth rate in mean sac diameter
> 1.2 mm/day
If yolk sac is 2-6 mm in diameter, it is always present when MSD is _____ on transabdominal us
> /= to 20
If yolk sac is 2-6 mm in diameter, it is always present when MSD is _____ on transvaginal US
> /= 16 mm
Where does the embryo develop?
Within the amniotic space
Yolk sac can be found in the
Chorionic fluid space
Excellent evidence of intrauterine pregnancy
Well-visualized double sac
A spherical cystic structure that is connected to the midgut of the embryo by a thin stalk, the vitelline duct
Yolk sac
Normal diameter of yolk sac
2-6 mm
Remnant of the connection of the vitelline duct to the distal ileum
Meckel diverticulum
Earliesr site of blood cell formation in the embyro
Yolk sac
Yolk sac is generally seen between what GA
5-12 weeks
Earliest demonstration of embryo is the ______, produced by the amniotic sac and yolk sac with the embryonic disc between them
Double bleb sign
Develops on the ovary at the site of the dominant follicle from which ovulation occurred
Corpus luteum
Secretes estrogens, progesterone and other hormones that are essential for establishing and maintaining pregnancy
Corpus luteum
Trimester of pregnancy wherein it includes cystic appearance if rhombencephalon and herniation of the gut into the base of umbilical cord
First
At what GA does the hindbrain forms a prominent cystic structure that becomes the normal fourth ventricle
6-8 weeks
Double bleb sign is formed by the
Yolk sac and amniotic sac
Cyst with intense ring of vascularity (ring of fire)
Corpus luteum
At what GA does the midgut herniates into the base of the umbilicus forming a physiologic omphalocele which is 6-9 mm in size
9-11 weeks
Occurence of vaginal bleeding and uterine cramping with a closed cervical OS
Threatened abortion
Presents with cervical dilatation and fetal or placental tissues within the cervical os
Inevitable abortion
Refers to presence of residual products of conception within the uterus
Incomplete abortion
Fetus has died, but remains in the uterus
Missed abortion
Defined as 3 or more successive spontaneous abortions
Habitual abortion
Pregnancy in which the embryo has died and is no longer visible or never developed
Anembryonic pregnancy or blighted ovum
A gestational sac is considered to be abnormal if it demonstrates the following
Large size without an embryo or yolk sac Distorted shape Irregular contour Thin or weak choriorecidual reaction Absence of double decidual sac Abnormal position
Strong evidence of abnormal sac development
Gestational sac of less than 1 mm/d MSD
Cardiac activity should be detected at what embryo size
More than 5mm
Major cause of pregnancy related maternal deaths
Ectopic pregnancy
Most common site of ectopic pregnancy
Isthmus
Concurrent intrauterine and extrauterine pregnancies
Heterotopic pregnancy
US finding in ectopic pregnancy that include demonstration of an extrauterine gestational sac appearing as a fluid-containing structure with an echogenic ring
Tubal ring sign
Common finding in the bleeding pregnant patient before 20 weeks GA. Believed to develop because of venous bleeding from separation of margin of placent
Subchorionic hemorrhage
Subchorionic hemorrhage is commonly seen beneath the
Chorion
Polypoid or pedunculated mass of retained placental tissues has been termed
Placental polyp
Echogenic mass within the uterine cavity following a spontaneous or induced abortion
Retained products of conception
