Placenta Lecture

Question 1

T embilical cord comes up from ___ the placenta and spreads across ___ ___ and branches into villi to increase the ___ ___. ____ ___ comes up into this plate and heads out into the villi.

Villi are covered with inner layer of _____ and an outer layer of _____ and are full of fetal blood, sit bathed in the lacuna, or lakes, which are full of ____ ____. The Mother’s ____ ____ spill the maternal blood into lacunae, this allows the maternal blood to come close to fetal blood, but the two do not mix.

Fetal blood gives off waste, absorbs nutrients and oxygen, and heads back through the cord to the ___. Maternal blood circulates, leaves the lacuna through ____ ____ ____ ____-.

Answer 1

below,

chorionic plate,

Surface area

Fetal blood

cytotrophoblast

syncytiotrophoblast

maternal blood

spiral arteries

fetus

lower pressure veinous drainage

Question 2

In the fetus, oxygenation occurs in the _____. The umbilical arteries carry _____ ____to the ____, and the umbilical vein carries ______ _____ back to the _____.

Answer 2

placenta

deoxygenated blood

placenta

oxygenated blood

fetus

Question 3

Wharton’s jelly: gelatinous substance that surrounds the _____; It is _____ ___, so it causes the blood vessels in the cord to _____ about 5 minutes after delivery

Answer 3

vessels

temp sensitive

collapse

Question 4

Single umbilical artery occur 1% of births. With this comes a small increase in chance for ___ _____, so number of vessels in the cord is counted at__-__ week ultrasound

Answer 4

genetic anomalies (like Downs syndrome)

19-20th week

Question 5

The fetus begins to make urine at about ___ ___ or so, and that pushes the ____ out to fuse with ____ ___ ___ (chorionic plate) & attaches to the wall or top of the uterus.

Answer 5

10 weeks

amnion

chorion placental disk

uterus

Question 6

A delivery without having the water broken and the sac intact is called?

Answer 6

en caul

Question 7

What hormones does the placenta make?

Answer 7

HCG (turns pregnancy test turn positive),

estrogen,

progesterone,

human placental lactogen

Question 8

Human placental lactrogen does what?

Answer 8

prepares the breasts for lactation

Question 9

Metabolically, the placenta makes?

Answer 9

Metabolic: makes glycogen, cholesterol.

Question 10

The placenta exchanges waste from the fetus, nutrition and oxygen from the mother by 4 mechanisms, what are they and describe what they might move?

Answer 10

simple diffusion- water, gases, some drugs (Psychoactive drugs like opiods)

Facilitated diffusion: glucose

active transport: amino acids

pinocytosis: Igs like for pertusis, whooping cough,

Question 11

Placenta is an isolation barrier- maintains sterile environment, maintains “immunologic privilege”- what does it prevent?

Some organisms can cross the placenta though, name 4:

Answer 11

keeps mom and baby’s blood from mixing; bc baby blood is foriegn to mom

CMV and rubella viruses

treponema pallidum

Listeria

Question 12

If an RH+ baby comes into contact with RH- moms antiRH antibodies, what could happen?

Answer 12

Erythroblastosis fetalis: severe anemia in baby- RBCs get lysed by maternal antibodies,

Question 13

Rhogam is synthetic____ against the Rh protein. After mom is injected, Rhogam can bind to any ____ ___ ___in maternal circulation and lyses those cells; mom’s cells are safe bc her RBCs are Rh negative. Mom’s immune system is not ____.

If a mom is Rh- whaen does she get rhogam?

Answer 13

antibodies

Rh+ fetal cells

sensitized

28weeks regardless of baby blood and the again after pregnancy if the baby was Rh+

Question 14

To prevent ___ ____, doctors look for the ____ on the ____ side of the placenta after placental delivery. If uterus empty, it will contract down to squeeze the ____ ___, stopping blood from entering where the lacuna used to be. However, if any tissue is retained, ____ ____ continue to try to fill lacuna with blood and _____ results

Answer 14

Maternal hemorrhage

cotyledons

maternal

spiral arteries

spiral arteries

hemorrhage

Question 15

During a Molar pregnancy, the ___ does not develop, but the _____ does, ___ fill with fluid- this needs to be evacuated.

Answer 15

fetus

placenta

villi

Question 16

Membraneous or velementous insertion occurs when the cord inserts off of the___ ____ completely and in the ____ instead. This is fine until the ____ ___ and membranes are no longer supported like a balloon. The vessels can kink because it is not protected by ____ ____ which is like ____ the baby because it cuts off ___ ____.

Answer 16

placental disk completely and in the membranes

water breaks

Whartons jelly

like choking the baby bc cuts off gas exchange

Question 17

An accessory or succinturiate lobe is an extra island of ____ tissue and can be _____ running in the membranes between the two _____ ____.

Answer 17

placental

vessels

placenta disks.

Question 18

Vasa previa is when vessels (from ____ or ___ ____) are below the baby’s head running across the ____ ____. These vessels may rupture if the ____ ___ and cause the baby to rapidly exsanguinate. These babies are usually delivered early at ____ weeks by cesarean section

Answer 18

accessory or succinturiate lobe

cervical opening

water breaks

exsanguinate

35 weeks

Question 19

Abnormal placentation occurs when trophoblastic tissue invades the maternal endometrium. Healthy maternal endometrium resists; ____ endometrium is not as good at resisting. If the pt has a history of many ____ ____ they are at higher risk. This is dangerous bc if the placenta does not detach after the baby delivers- still has a vast ___ ____ can ______ very dangerously.

Answer 19

Abnormal placentation

scarred

c sections

blood supply

hemorrhage

Question 20

what are the types of abnormal placentaion? describe each

Answer 20

Placenta accreta- placenta implants over previous cesarean section scar abnormally attached to uterine myometrium, does not neatly separate after delivery

Placenta increta grows deeply into uterine wall

Placental Percreta- growing all the way through the uterus, invades bowel or bladder

Question 21

If abnormal placentation is diagnosed early, what preventative actions can be taken? (5)

Answer 21

1. More iron intake in pregnancy,
2. may transfuse her before delivery,
3. make an extra big incision so we can work quickly,
4. use extra medicines that can help her tissue clot,
5. have a cell-saver device to suction up the blood, spin it down and transfuse her own blood back to her.

Question 22

_____ is when the placenta separates prematurely. This can be caused by _____, ____ ____ ____ or _____. It is very ____ for the mother and usually the baby needs to be ___ _____.

Answer 22

Cociane

High BP

trauma

painful

emergently delivered

Question 23

Twin-twin transfusion syndrome occurs in placenta of ____ twins where a ___ ____vessel from one baby connects to a ___ ___ vessel from the other baby and allows blood run from one baby to the other. The “donor” twin unable to ____ or to make much ___ while the recipient twin becomes fluid _____.

Options for management include ___ ___, or fetal surgery- laser_____ of ____ ____.

Answer 23

monochorionic

high pressure

low pressure

grow or make much fluid

overloaded

early delivery

ablation of vasculation connections

Question 24

The amniotic fluid provides a ____ for the fetus and the cord, allows fetal ____, and contains ____ ___ for the ___ that are made in the ___ ___, breathed in by developing fetus

Answer 24

cushion

movement

growth factor

lungs

fetal kidney

Question 25

Potter’s syndrome is when ___ ____ occurs; what does this mean?

There will be no ___ __, no ___, and no ___ __. These babies live for minutes to hours ____ ___. This syndrome is not compatible with life.

Answer 25

renal agenesis-

kidneys do not form at all

no urine output- no fluid- no lung development

after delivery