Placenta praevia

Question 1

Definitions of Praevia

Answer 1

Praevia- covering internal os
Low lying- within 20mm of internal os
Normal >20mm of internal os

Question 2

RF to get praevia

Answer 2

Prev praevia
Prev CS- 1 prev- 1%, 2 prev 1.7%, 3 prev- 2.8%
ART
Smoking
Mat age >40
<12m of birth after CS

Question 3

Diagnosis of praevia

Answer 3

TV Scan at 20 weeks
32 weeks, if still low then 36 weeks.

Also check cervical length, if <25mm- higher risk of PTB and bleeding.

Question 4

Management

Answer 4

Individualised care
Advise- no intercourse
VTE- esp when in hospital, balance risk and benefits.
Tocolysis- only for time for steroids and if mum/baby are well

DO NOT use cerclage

Question 5

RF with praevia

Answer 5

Preterm birth
APH and PPH
Blood tx (12x more likely)
CS and hysterectomy risks
Risk of needing GA

Question 6

CS in praevia

Answer 6

USS to check placenta position
Make incision away from the placenta- vertical if needed
Early hysterectomy

Question 7

Definition of accreta

Answer 7

Accreta- only myometrium
Increta- myometrium and serosa
Pancreta- Perforates the entire uterine wall

Question 8

Risk of accreta if praevia and prev CS

Answer 8

1 prev- 3%
2 prev- 11%
3 prev- 40%

Question 9

Diagnosis of accreta

Answer 9

On USS

Most specific- bladder wall interruption,
most sensitive- abnormal vasculature

MRI
Abnormal uterine bulging
Dark intraplacental bands

Question 10

RF of accreta

Answer 10

Praevia
Prev CS
Prev uterine surg- myomectomy, MROP, curretage
PN endometritis
Bicornuate uterus
Submucosal fibroids