APH

Question 1

List five risk factors for placenta previa.

Answer 1

Previous placenta previa
Previous CS, especially < 12 months ago
Previous uterine surgery (myomectomy, D&amp;C)
Multiple gestation
Parity > 3
Smoking
Cocaine use
IVF
AMA

Question 2

List three criteria for outpatient management of placenta previa.

Answer 2

Reliable patient
No vaginal bleeding
Hemodynamically stable
Lives a short distance from the hospital
Transport to hospital readily available

Question 3

List three ways of managing placental site bleeding at CS.

Answer 3

Oversew placental bed
Injection of vasopressin
Bakri balloon
Hysterectomy

Question 4

List four risk factors for vasa previa.

Answer 4

Velamentous cord insertion (1 in 50) - this is a prerequisite for vasa previa
Bilobate or succenturiate placenta
Multiple gestation
IVF
Placenta previa or low-lying placenta
Fetal anomalies - renal, SUA, NTD
Prematurity
IUGR

Question 5

Define vasa previa.

Answer 5

Umbilical blood vessels (unsupported by umbilical cord or placenta) traverse the membranes in the lower uterine segment above the cervix & below the presenting part

Question 6

Describe the management of vasa previa diagnosed on anatomy scan.

Answer 6

Steroids at 28-32 weeks
Hospitalization at 30-32 weeks
Antenatal peds consult
Serial TV US to assess for possible regression of vasa previa
CS at 35-36 weeks (or immediately following onset of labour/PPROM)

Question 7

For a woman with a placenta previa or low-lying placenta on second trimester US, at what gestational age does US best predict likelihood of safe vaginal delivery?

Answer 7

35-36 weeks

Question 8

You admit a hemodynamically stable woman with bleeding from a placenta previa at 24 weeks. Her bleeding resolves and you prepare to discharge her. She asks whether her single episode of bleeding means she is more likely to deliver significantly preterm. What would you counsel her?

Answer 8

Clinical outcomes of placenta previa are highly variable, can’t be confidently predicted
Approx 75% of women experience at least one episode of bleeding (median GA 29 weeks), majority remain stable (median GA for delivery 36 weeks)

Question 9

List four ultrasound findings that would lead you to suspect placenta accreta.

Answer 9

Loss of the hypoechogenic space between placenta & myometrium
Bladder line interruption
Presence of placental lacunae
Myometrial thickness < 1 mm

Question 10

List three conservative treatments that might be considered for a woman with placenta accreta who wishes to preserve her fertility.

Answer 10

Leave placenta in situ (consider balloon catheterization of uterine vessels pre-op & embolization post-op)
Uterine or internal iliac artery ligation
Curettage or over-sewing of placental bed
Uterovaginal packing