Placenta Previa, morbidly adherent, abruption and vasa previa

Question 1

What is placenta previa?
How many births does it affect?

Answer 1

When the placenta lies low in the uterus - may even cover the cervical OS

4-5/1000 births

Question 2

What are the 4 types of placenta previa?

Answer 2

1 - low lying placenta - in lower segment 20mm or less of the internal OS

2 - Marginal Placenta: touching internal OS

3 - Partial Previa: covering internal OS

4 - Complete Previa: Total OS covered

Question 3

RF of placenta previa?

Answer 3

Multiple pregnancies, miscarriage pHx, C sections, high age, maternal smoking, IVF, PMHx

Question 4

Sx of placenta previa?

Answer 4

3/3 painless PV bleeding, bright red blood
Suspected after >24 weeks

Question 5

Diagnosis of placenta previa?

Answer 5

ID on Anomaly scan TV USS (18-20+6 weeks),
do NOT do PV exam
Then at 34 week scan

Question 6

Treatment of placenta previa?

Answer 6

grade 1 - consider vaginal birth with Obs

grade 2-4 - consider c section

Question 7

What normally happens to the placenta in pregnancy?

Answer 7

Placenta normally migrates up during pregnancy

Question 8

What is a morbidly adherent placenta?

Answer 8

Abnormal implantation at basal plate —> placenta fails to detach from uterine wall - massive obstetric haemorrhage

Question 9

RF for MAP?

Answer 9

Placenta previa, c section, uterine surgery (eg, D+C), Multiparous, IVF

Question 10

dx of MAP?

Answer 10

TV USS anomaly scan - loss of normal hypo echoic retroplacental zone + placental lacunae

Question 11

Tx of MAP?

Answer 11

c - section MUST be done, most often + hysterectomy + group and save with transfusion as increased blood loss

Question 12

Complication of MAP?

Answer 12

Heavy PPH (>2000ML often)

Prematurity (deliver 35-37 weeks to reduce haemorrhage risk)

Placental infection if not hysterectomy done

Question 13

What is placental abruption?

Answer 13

Separation of placenta from the endometrial wall causing bleeding

Question 14

What is the most common cause of bleeding in third trimester?

Answer 14

Placental abruption

Question 15

RF for placental abruption?

Answer 15

smoking
cocaine use
Htn
trauma
multiparty
polyhydromnios

Question 16

Sx of placental abruption?

Answer 16

3/3 painful pv dark red bleed
Hard woody uterus - often pain not proportional to apparent blood loss (due to occult blood)

Question 17

Dx of placental abruption?

Answer 17

USS (rule out vasa previa) - likely normal

Question 18

Tx for stable and unstable placental abruption?

Answer 18

stable - observe
unstable - maternal/foetal distress - cat 1 c section

Question 19

Comp of placental abruption?

Answer 19

DIC!!!!!!
Prematurity
M-F death

Question 20

What is vasa previa?

Answer 20

where the foetal vessels unprotected by the umbilical cord or placental tissue run dangerously close to or across the internal cervical OS, vessels prone to rupture in ROM

Question 21

RF for vasa previa?

Answer 21

IVF
Placenta previa
multiple pregnancies

Question 22

Sx of vasa previa?

Answer 22

Bright painless heavy PV bleed 3/3
ROM
foetal bradycardia

Question 23

Dx of vasa previa?

Answer 23

USS - Shows Umbilical arteries presenting

Question 24

Tx of vasa previa?

Answer 24

need cat 1 c section
- foetal death highly likely