placenta praevia

Question 1

definition

Answer 1

Placenta praevia is where the placenta is attached in the lower portion of the uterus, lower than the presenting part of the fetus

Question 2

three main causes of antepartum haemorrhage

Answer 2

placenta praevia
placental abruption
vasa praevia

Question 3

low lying placenta vs placenta praevia

Answer 3

Low-lying placenta is used when the placenta is within 20mm of the internal cervical os
Placenta praevia is used only when the placenta is over the internal cervical os

Question 4

risk factors for placenta praevia

Answer 4

Previous caesarean sections
Previous placenta praevia
Older maternal age
Maternal smoking
Structural uterine abnormalities (e.g. fibroids)
Assisted reproduction (e.g. IVF)

Question 5

complications

Answer 5

Antepartum haemorrhage
Emergency caesarean section
Emergency hysterectomy
Maternal anaemia and transfusions
Preterm birth and low birth weight
Stillbirth

Question 6

when is placenta praevia diagnosied

Answer 6

20 week anomaly scan

Question 7

symptoms and signs

Answer 7

painless vaginal bleeding around 36 weeks
shock in proportion to visual loss
non tender uterus
coagulation problems are rare
fetal heart sounds normal
non tender and non painful

Question 8

monitoring and management

Answer 8

TVUSS
rescan at 32 weeks, and every 2 weeks with final scan at 36-37 weeks

elective c section : grade 3 / 4
grade 1 : vaginal delivery can be trialled

Question 9

Placenta praevia with bleeding

Answer 9

admit
ABC approach to stabilise the woman
if not able to stabilise → emergency caesarean section
if in labour or term reached → emergency caesarean section

Question 10

grading

Answer 10

I - placenta reaches lower segment but not the internal os
II - placenta reaches internal os but doesn’t cover it
III - placenta covers the internal os before dilation but not when dilated
IV (‘major’) - placenta completely covers the internal os