Flashcards - Placenta Praevia and Placenta Accreta -Answers based on RCOG Green Top Guideline (GTG) 27a (version Sept 2018)

Question 1

The term placenta praevia is used when placenta lies _____

Answer

Directly over the internal os.

Question 2

The term low – lying placenta should be used for placental edge less than ___ from the internal os.

Answer

20 mm

Question 3

The term low – lying placenta should be used for placental edge less than 20 mm from the internal os for pregnancies more than ___

Answer

16 weeks

Question 4

Follow up ultrasound after detection of low – lying placenta at anomaly scan is done at ____weeks of gestation

Answer

32 weeks (including a TVS)

Question 5

For persistent low – lying placenta or placena praevia at 32 weeks, additional TVS done at _____.

Answer

36 weeks

Question 6

Role of cervical length measurement in asymptomatic women with placenta praevia

Answer

Is to facilitate management decisions (short cervix on TVS before 34 weeks -↑ risk of preterm emerg delivery and massive h’age at caesarean section)

Question 7

The use of cervical cerclage to reduce bleeding and prolong pregnancy with placenta praevia

Answer

Is not supported outside clinical trial

Question 8

Recommendation regarding antenatal corticosteroid therapy with low-lying placenta or placenta praevia

Answer

Single dose recommended between 34+0 and 35+6 weeks

Question 9

Role of tocolysis with symptomatic placenta praevia

Answer

Considered for 48 hours to facilitate administeration of antenatal steroids

Question 10

For uncomplicated placenta praevia, when should delivery be timed?

Answer

Between 36+0 and 37+0 weeks of gestation

Question 11

When should delivery be timed for placenta praevia with hisory of vaginal bleeding or risk factors for preterm delivery?

Answer

Between 34+0 and 36+6 weeks of gestation

Question 12

Which anaesthesia is most appropriate for women with placenta praevia or low-lying placenta?

Answer

Regional anaesthesia – safe. Counselling that GA may be needed.

Question 13

Surgical approach if fetus is in trasverse lie, below 28 weeks gestation.

Answer

Vertical skin and/or uterine incisions

Question 14

Major risk factors for placenta accreta spectrum

Answer

History of accreta in prev pregnancy, Prev CS/uterine surgery, Repeated endometrial currettage

Question 15

Role of MRI in diagnosis of accreta spectrum?

Answer

To complement USS esp with posterior placenta &/or parametrial invasion.

Question 16

When should women be screened for placenta accreta?

Answer

H/o prev CS + anterior low-lying placenta or praevia on anomaly scan

Question 17

Timing of delivery for placenta accreta without other risk factors

Answer

Between 35+0 and 36+6 weeks

Question 18

Anaesthesia for women with placenta accreta

Answer

Regional anaesthesia – safe. Counselling that GA may be needed.

Question 19

Surgical approach for women with placenta accreta

Answer

Caesarean section hysterectomy with placenta left in situ

Question 20

When is uterus preserving surgery/partial myometrial resection with placenta accreta appropriate?

Answer

Extent limited in depth and surface area, entire placental area accessible and visualised

Question 21

Placenta accreta locations when uterus preserving surgery is suitable.

Answer

Completely anterior, fundal or posterior without deep pelvic invasion.

Question 22

Role of ureteric stents with placenta accreta spectrum

Answer

When urinary bladder is invaded by placental tissue

Question 23

If uterine preservation desired with placenta accreta

Answer

Consider leaving placenta in situ.

Question 24

Follow up if placenta left in situ

Answer

Regular review, USS and emergency access (if bleeding or infection).

Question 25

Should Methotrexate be used for expectant management with placenta in situ?

Answer

NOT to be used as unproven benefit and significant adverse effects

Question 26

Role of interventional radiology with acccreta

Answer

When declining blood transfusion.

Question 27

Management of undiagnosed placenta accreta at elective repeat CS

Answer

Delay surgery – close abdomen + transfer to specialist unit.

Question 28

Unsuspected placenta accreta diagnosed after birth of baby

Answer

Leave placenta in situ, perform emergency hysterectomy.

Question 29

Incidence of placenta praevia at term

Answer

1 in 200 pregnancies

Question 30

Placenta accreta was first defined in 1937 by

Answer

Irving and Hertig

Question 31

Placenta ‘creta’ or ‘adherenta’ is in which

Answer

Villi adhere superficially to the myometrium without interposing decidua

Question 32

Placenta ‘increta’ is in which

Answer

Villi penetrate deeply into the uterine myometrium down to the serosa.

Question 33

Placenta ‘percreta’ is in which

Answer

Villi perforate through the entire uterine wall & may invade the surrounding pelvic organs, such as bladder.

Question 34

Prevalence of placenta accreta in range of

Answer

Between 1 in 300 to 1 in 2000 pregnancies

Question 35

Risk factors for placenta praevia

Answer

CS (risk rises as number of CS increases)

ART

Smoking

Question 36

High risk of emergency transfusion + no clinically significant alloantibodies….how frequently should group and screen samples be sent?

Answer

Once a week (to exclude or identify any new antibody formation)

Question 37

Risk of accreta placentation after 1 CS is

Answer

Question 38

Risk of accreta placentation after 2 CS is

Answer

11%

Question 39

Risk of accreta placentation after 3 CS is

Answer

40%

Question 40

Risk of accreta placentation after 4 CS is

Answer

61 %

Question 41

Risk of accreta placentation after 5 CS is

Answer

67 %

Question 42

Risk of accreta placentation after 6 CS is

Answer

67 % (for 5 or more CS)

Question 43

Incidence of massive haemorrhage in placenta praevia

Answer

21%

Question 44

Increase in risk of placenta praevia after IVF as compared to natural pregnancies

Answer

3 – fold

Courses Blogs

Question 1

The term placenta praevia is used when placenta lies _____

Answer

Directly over the internal os.

Question 2

The term low – lying placenta should be used for placental edge less than ___ from the internal os.

Answer

20 mm

Question 3

The term low – lying placenta should be used for placental edge less than 20 mm from the internal os for pregnancies more than ___

Answer

16 weeks

Question 4

Follow up ultrasound after detection of low – lying placenta at anomaly scan is done at ____weeks of gestation

Answer

32 weeks (including a TVS)

Question 5

For persistent low – lying placenta or placena praevia at 32 weeks, additional TVS done at _____.

Answer

36 weeks

Question 6

Role of cervical length measurement in asymptomatic women with placenta praevia

Answer

Is to facilitate management decisions (short cervix on TVS before 34 weeks -↑ risk of preterm emerg delivery and massive h’age at caesarean section)

Question 7

The use of cervical cerclage to reduce bleeding and prolong pregnancy with placenta praevia

Answer

Is not supported outside clinical trial

Question 8

Recommendation regarding antenatal corticosteroid therapy with low-lying placenta or placenta praevia

Answer

Single dose recommended between 34+0 and 35+6 weeks

Question 9

Role of tocolysis with symptomatic placenta praevia

Answer

Considered for 48 hours to facilitate administeration of antenatal steroids

Question 10

For uncomplicated placenta praevia, when should delivery be timed?

Answer

Between 36+0 and 37+0 weeks of gestation

Question 11

When should delivery be timed for placenta praevia with hisory of vaginal bleeding or risk factors for preterm delivery?

Answer

Between 34+0 and 36+6 weeks of gestation

Question 12

Which anaesthesia is most appropriate for women with placenta praevia or low-lying placenta?

Answer

Regional anaesthesia – safe. Counselling that GA may be needed.

Question 13

Surgical approach if fetus is in trasverse lie, below 28 weeks gestation.

Answer

Vertical skin and/or uterine incisions

Question 14

Major risk factors for placenta accreta spectrum

Answer

Question 15

Role of MRI in diagnosis of accreta spectrum?

Answer

To complement USS esp with posterior placenta &/or parametrial invasion.

Question 16

When should women be screened for placenta accreta?

Answer

H/o prev CS + anterior low-lying placenta or praevia on anomaly scan

Question 17

Timing of delivery for placenta accreta without other risk factors

Answer

Between 35+0 and 36+6 weeks

Question 18

Anaesthesia for women with placenta accreta

Answer

Regional anaesthesia – safe. Counselling that GA may be needed.

Question 19

Surgical approach for women with placenta accreta

Answer

Caesarean section hysterectomy with placenta left in situ

Question 20

When is uterus preserving surgery/partial myometrial resection with placenta accreta appropriate?

Answer

Question 21