Placenta Praevia
Placenta
that has implanted in part or all of
the
lower uterine segment encroaching
upon
or covering the internal cervical os.
Responsible
for 15-20% of APH’s
Haemorrhage
is likely in the third trimester
as
the lower segment grows and thins or
the
cervix dilates.
With
the increase in LSCS the clinician
should
consider placenta accreta, increta
&
percreta with placenta praevia
Grading
Grade
1 ( 1st Degree)
Part
of placenta lies in the lower segment but does
not
reach os
Grade
2 ( 2nd Degree)
The
lower margin of the placenta reaches the internal
os
but does not cover it
Grade
3 ( 3rd Degree)
The
placenta covers the os
Grade
4 ( 4th Degree)
The
placenta lies centrally over the os
Risk Factors:
1-multiple
pregnancy
2-multigravida
3-old
age
4-previous CS
5-previous
PP
6-uterine
damage by curettage
7-uterine
anomaly
Clinical Features
Bleeding
without abdominal pain or uterine
tenderness,
usually bright red
Usually
between 34-38 wks (20% before 28
weeks)
May
be associated with contractions
Bleeding
usually recurs often increasing in
severity
with increasing gestational age
Not
usually precipitated by any one factor,
coitus,
etc.
30%
women with placenta praevia will not have
a
APH
Manegement:
*resuscitation
*according
to the bleeding:
**if
sever:terminat pregnancy regardless
gestational
age
***if
not sever:control the bleeding then
according
to the GA
**if
term:terminat
**if
not:until termthen terminat
Cx:
1:shock
2:PPH
3:preterm
labour
4:recrrence
5:DIC
Vasa Praevia
Rare
- 1 in 3000
Fetal
vessels run in the membrane below the presenting
fetal
part, unsupported by placental tissue or umbilical
cord
Spontaneous
or artificial rupture of membranes - rupture
these
vessels - fetal exsanguination.
Hypoxia
if the vessels are compressed between baby &
birth
canal.
Fetal
mortality 33-100%, if not diagnosed prenatally.
Antenatal Diagnosis
.
ultrasound
checking placental cord connection.
Can
be diagnosed as early as 16 weeks .
All
suspected cases should be checked for vasa praevia
transvaginal
scan with color doppler.
Doppler
scan to detect Vasa praevia - 1
Management
If
diagnosed prenatally
tocolytics,
bedrest
no
vaginal exams
avoid
heavy lifting, straining during bowel movement
regular
scans
Planned
cesarean section can circumvent fetal risks.
Delivery
can be planned early enough to avoid
emergency,
but late enough to avoid prematurity
Baby
requires aggressive resuscitation & blood
transfusion
Management
If
PV bleeding intrapartum
Speculum
- fetal vessels.
Investigate
for the source of bleeding
Apt
test - fetal hemoglobin is alkali resistant.
Wright
stain of blood smear.
If
fetal bleeding confirmed, immediate cesarean section.