Lec 36

Question 1

What is the placenta?

Answer 1

A fetomaternal organ that has two components : fetal & maternal

Question 2

Where does the fetal develop from ?

Answer 2

Villous chorion

Question 3

Where does the maternal develop from ?

Answer 3

Endometrium , decidua basalis

Question 4

the formation of the chronic villi occurs when :

Answer 4

the cavities appearing within the syncytiotrophoblast from intravillous spaces are filled with maternal blood

Question 5

fetal blood vessels develop in —— , which is surrounded by intravillous space

Answer 5

chorionic villi

Question 6

the bulk of the chorionic villi which remains along with the uterine endometrium ( decidua basalis )Form ——

Answer 6

placenta

Question 7

What’s The decidua ?

Answer 7

the endometrium of pregnant uterus

Question 8

The term the decidua means

Answer 8

falling off , shed , sloughed off

Question 9

by the end of the — month , the amniotic cavity is enlarged and the uterine cavity is decreased in size.

Answer 9

third

Question 10

What is the function of the placenta?

Answer 10

The primary function is to serve as an organ for exchange between the fetus and mother

Question 11

normally the maternal blood and fetal blood —— mix

Answer 11

do not

Question 12

spiral branches of the uterine arteries bring —— blood to intravillous space

Answer 12

oxygenated

Question 12

The umbilical arteries take —— from the embryo to the villi .

Answer 12

deoxygenated blood

Question 13

the —— side exhibits 15 - 20 cotyledons separated by decidual septa

Answer 13

maternal

Question 13

gas exchange & transfer of other molecules occurs across the ——

Answer 13

villi

Question 14

fetal surface is covered by the ——.

Answer 14

amnion

Question 15

The fatal surface is ——
The maternal surface is ——

Answer 15

shiny
dull

Question 16

What is placenta increta

Answer 16

invade deeply in the myometrium

Question 16

Clinical considerations for placental abnormalities are :

Answer 16

1- placenta accreta
2- placenta increta
3- placenta percreta

Question 16

What is placenta accreta ?

Answer 16

abnormal adherence of chronic will lie to the myometrium

Question 17

What is placenta percreta ?

Answer 17

chorionic will penetrate to full thickness of the myometrium presentation leading to retained placenta and postpartum haemorrhage

Question 18

What is placenta previa ?

Answer 18

when the blastocyst implants close to/overlying the internal opening of the cervix

Question 19

What leads to late pregnancy bleeding?

Answer 19

Placenta previa

Question 20

The umbilical cord is the only connection between the fetus and ———
the —— in the umbilical cord connect the —— circulation with the —— circulation.
The umbilical cord has 2 umbilical —— and 1 umbilical —— that are embedded in a mucoid connective tissue called ———

Answer 20

placenta/mother
vessels , placental , fetal
arteries , vein , Wharton jelly

Question 21

The definitive umbilical cord at term is —— , 1-2 cm in diameter , 50 - 60 cm long.

Answer 21

pearl White

Question 21

the amnion enlarges + obliterates the chorionic cavity between weeks ——— to create the amniochorionic membrane that —— during labour. The amount of amniotic fluid is gradually —— during pregnancy from 50 ml at week — to 1000 ml at term The amnion is a —— fluid so there must be a —— between secretion and clearance

Answer 21

4 and 8 , rapture increased , 12 dynamic , balance

Question 22

The sources & production of amniotic fluid are :

Answer 22

1-cells of amniotic membrane itself 2- fetal urine 3- fetal lung secretions

Question 23

since the AF is —— produced. It must be —— resorbed. This occurs by the following sequence :

Answer 23

constantly constantly 1- the fetus swallow amniotic fluid. 2- The amniotic fluid is absorbed into fetal blood through the GIT ,blood ,kidneys ,urine 3- excess amniotic fluid is removed by the placenta 4- passed into maternal Blood.

Question 24

The significance of amniotic fluid :

Answer 24

1- It acts as a protective cushion to the embryo / fetus 2- absorbs trauma and acts as a barrier to infection 3- prevents adherence of the embryo to the amnion 4- allows for fetal movement

Question 25

the —— of amniotic fluid at various stages of pregnancy can be indicative of congenital malformations

Answer 25

amount

Question 26

what might go wrong to the amniotic fluid ?

Answer 26

1- Oligohydramnios: ( 400 ml in late pregnancy ) maybe indicative of renal agenesis 2- Polyhydramnios: ( 2000 ml in late pregnancy ) maybe indicative of either anencephaly or esophageal atresia , it is commonly associated with maternal diabetes

Question 27

What are the causes of Oligohydramnios :

Answer 27

1- reduced fetal urine output -> Renal abnormalities { kidney agenesis } 2- increased clearance -> premature rupture of membrane -> chromosomal abnormalities

Question 28

What are the causes of Polyhydramnios :

Answer 28

1- reduced clearance / increased accumulation -> reduced fetal swallowing { fetal CNS malformation , anencephaly } -> obstructive anomalies of the GI { esophageal atresia } 2- increased production -> multiple pregnancy , DM , 50% idiopathic

Question 29

when a mother gives to 2 fetus in a single pregnancy is

Answer 29

Twinning

Question 30

What results in dizygotic twins / Fraternal ?

Answer 30

Women’s ovaries release 2 eggs at once that are fertilised by 2 different sperm , the result is non- identical or fraternal twins

Question 31

what results in monozygotic twins/identical ?

Answer 31

[ from one zygote, single sperm / single ovum ]that splits into 2 , they have identical genetic material ,similarity in appearance, same gender, same blood grouping

Question 32

Dizygotic twins and 35% of the monozygotic twins have — amniotic sacs , and — chorions

Answer 32

2 , 2

Question 33

the degree of which —— twins share membranes depends on the stage of development at which the originally single embryo —— into two embryos

Answer 33

monozygotic separates

Question 34

if splitting occurs at the two-cell stage of cleavage the twins will develop as —— as dizygotic twins

Answer 34

separately

Question 35

if splitting occurs at early blastocyst stage ( inner cell mass ) This leads to ——— ,the embryos will share a ———— but occupy separate amnions

Answer 35

2 inner cell masses single chorion and placenta

Question 36

if splitting occurs at late blastocyst stage ( bilaminar disc ) the twins will share the ———

Answer 36

chorion and the amnion

Question 37

At day 0 - 4 if they separate they share the same —— At day 5 - 8 if they separate they share the same —— At day 9 - 12 if they separate they share the same ———— [ rare ] Above 13 days if they separate they share ————— [ rare ]

Answer 37

Sperm chorion & sperm amnion & chorion & sperm body parts & amnion & chorion & sperm

Question 38

If the separation of the developing embryo at later stages is incomplete , this may result in formation of —— twins , they may be united at :

Answer 38

conjoined 1- thorax 2- head 3- sacral region

Question 39

If they are joined at the thorax they have —— [ the most common type ] If they are joined at the head they have —— If they are joined at the sacral region they have ——

Answer 39

thoracopagus craniopagus pygopagus

Question 40

twin pregnancy have high incidence of :

Answer 40

1- perinatal mortality 2- preterm delivery 3- small weight at birth 4- twin transfusion syndrome

Question 41

What is twin transfusion syndrome ?

Answer 41

when they share the same placenta in 5 - 15% of monochorionic monozygotic twins

Question 42

Parental diagnostic procedures are :

Answer 42

1- Ultrasonography 2- maternal serum screening 3- amniocentesis 4- chorionic villus sampling

Question 43

ultrasonography or ultrasound is a —— technique

Answer 43

non-invasive

Question 44

What are the important parameters revealed by ultrasound :

Answer 44

1-confirm fetal viability 2- fetal age & growth 3- presence / absence of congenital anomalies ( NTDs, abdominal wall defects, heart and facial defects ) 4- amount of amniotic fluid can be identified 5- placental position & umbilical blood flow 6- identify multiple gestation

Question 45

Maternal serum screening involves —— concentration & human chorionic gonadotropin —— ( is it available or not , are the levels of it high/normal/low )

Answer 45

alpha fetoprotein , hCG

Question 46

the highest levels of AFP normally occur during —— week of pregnancy later its concentration decreases

Answer 46

12 to 15

Question 47

A high level of AFP after week 16 usually indicate

Answer 47

1- neural tube defects ( spina bifida or anencephaly ) 2- Gastroschisis 3- bladder exstrophy

Question 48

AFP concentration—— in Down syndrome

Answer 48

Decreases

Question 49

amniocentesis is performed from —— week of pregnancy amniotic fluid is withdrawn a needle inserted by the —— . The fetal cells are cultured for —— purposes.( karyotype analysis to diagnose chromosomal abnormalities )

Answer 49

15 - 20 abdominal wall testing

Question 50

The CVS is conducted from —— week of pregnancy. The tube is inserted through the —— in between uterus and chorion with —— guidance A sample of —— is taken

Answer 50

8 to 12 vagina , ultrasound chorionic villi

Question 51

Indications for using these invasive tests

Answer 51

1. advanced maternal age above 35 2. previous family history of a genetic problem 3.presence of maternal disease { diabetes } 4. abnormal ultrasound or serum screening.

Question 52

Indications for using these invasive tests

Answer 52

1. advanced maternal age above 35 2. previous family history of a genetic problem 3.presence of maternal disease { diabetes } 4. abnormal ultrasound or serum screening.