chapter 56 Flashcards
what are the 3 decidual ?
- decidua basalis
- decidual capsularis
- decidual vera
chorion frondosum :
forms fetal part of placenta: contains villi
chorion laeve:
nonvillios part of chorion around gestational sac.
chorionic plate:
fetal surface of placenta
basal plate:
maternal surface of placenta
fetal placenta cells come from
cytotrophoblastic shell and anchoring villi.
approximately 40 % of fetal cardiac out put is directed through ____?
umbilical circulation
infraction is?
obstruction of blood flow.
placenta membranes is called ____?
barrier
battledore?
abnormal cordal attachments to placenta: edge of placenta.
when does the secondary yolk sac form ?
after the regression of primary yolk sac.
by 9 weeks yolk sac should be ___ mm
5 mm
what is the most common implantation of the placenta?
fundal posterior
amnion fuses with chorion by which week?
16th week
in 1st trimenster the fetus begins to ___?
excrete urine to fill amniotic cavity
amniotic fluid functions are:
permitting fetus room to move
allowing lungs to develop properly
serving as protective buffer for fetus
maintaining constant fetal body temp.
the umbilical cord is formed during 1st ___ weeks of gestation.
5 weeks
what is the percentage that the fetus has a single umbilical cord abnormality ?
25 to 50 %
the second surface is ____, the maternal portion of the placenta.
basal plate
Normal placenta should not exceed?
4 cm
placenta is separate from ____?
myometrium
If the bladder is full, what impression can it present?
impression of previa- falsely elongated
what is the best way to identify lower uterine segment,
transvaginal
high resistance flow is seen when there is ?
stenosis