2. DEFINITION
APH is defined as bleeding from or into the genital tract after the
28th week of pregnancy but before the birth of the baby ( the first
and second stage of labor are thus included )
28th week is taken arbitrarily as the lower limit of fetal viability
Incidence – 3 %
4. PLACENTA PREVIA
When the placenta is implanted partially or completely over the
lower uterine segment ( over and adjacent to the internal os ) is
called placenta previa
The term previa ( L, in front of) denotes the position of the
placenta in relation to the presenting part
Incidence- 0.5 to 1%
5. HIGH RISK FACTORS
Multiparity
Maternal age - >35 years
Race – Asian women
Maternal factors – infertility treatment
Presence of uterine segment – C section, myomectomy, hysterectomy
Prior curettage
Prior placenta previa
Multiple pregnancy
Placenta size& abnormality – succenturiate lobes, big placenta
Smoking – causes placental hypertrophy to composite CO induced hypoxemia
6. ETIOLOGY
Dropping down theory- The fertilized ovum drops down and is
implanted in the lower segment. Poor decidual reaction in the upper
segment may be the cause. Failure of zona pellucida to disappear in
time can be a hypothetical possibility. This explains the formation of
central placenta previa
Persistence of chorionic activity – in decidua capsularis and it’s
subsequent development into capsular placenta which comes in contact
with decidua vera of the lower segment
Defective decidua
Big surface area of the placenta
7. Placenta
The placenta may be large and thin. This is often tongue shaped extension from the main placental
mass. Extensive areas of degeneration with infarction and calcification may evident.
The placenta may be morbidly adherent due to poor decidual formation in the lower segment.
Umbilical cord
The cord may be attached to the margin or into the membranes. The insertion of the cord may be close
to the internal os or the fetus blood vessels may run across the internal os in velamentous insertion due
to poor placental formation
Lower uterine segment
Due to increased vascularity, the lower uterine segment and the cervix becomes soft and more friable.
9. DANGEROUS PLACENTA PREVIA
Dangerous placenta previa is the name given to the type-II posterior placenta
previa
Because of curved birth canal major thickness of the placenta overlies the
sacral promontory, thereby diminishing the antero-posterior diameter of the
inlet and prevents engagement of the presenting part. This hinders effective
compression of the separated placenta to stop bleeding
Placenta is more likely to compressed if vaginal delivery is allowed
More chance of cord compression or cord prolapsed
This may lead to fetal anoxia or even death
10. CAUSE OF BLEEDING
As the placenta growth slows down in later months and the lower
segment progressively dilates, the inelastic is sheared off the wall
of the lower segment opening up of uteroplacental vessels
bleeding ( inevitable)
Separation of the placenta may be provoked by trauma including
vaginal examination, coital act, external version or during high
rupture of the membranes
The blood is almost always maternal, although fetal blood may
escape from the torn villi
11. PLACENTAL MIGRATION
The term placental migration could be explained in two ways:
With progressive increase in the length of lower uterine segment,
the lower placental edge relocates away from the cervical os .
Due to trophotropism (growth of trophoblastic tissue towards the
fundus), there is resolution of placenta previa.
13. SIGNS
Abdominal examination
Size of the uterus is proportionate to the period of gestation.
The uterus feels relaxed, soft and elastic without any localized
areas of tenderness.
Persistence of malpresentations
The head is floating in contrast to the period of gestation.
14. The FHS is usually present unless there is major separation of the placenta.
Slowing of the FHS on pressing the head down into the pelvis which soon
recovers promptly as the pressure is released is suggestive of the presence of
low lying placenta specially of posterior type it is known as Stallworthy’s sign.
Vulval inspection :
Only inspection is to be done to check whether bleeding is still occurring or has
ceased
In placenta previa the blood is bright red as the bleeding occurs from the
separated uteroplacental sinuses close to the cervical opening and escape out
immediately.
Vaginal examination must not be done outside the operation theatre in the
hospital
15. DIAGNOSIS
History and clinical features
Painless and recurrent vaginal bleeding in the second half of pregnancy
should be taken as placenta previa unless provoked otherwise.
Placentography
Sonographyhy
1. Transabdominal --The accuracy after 30th week of gestation is about 98%
2. Transvaginal(TVS)--The probe is very close to the target area. It is more
accurate than TAS
3. Transperineal(TPS)--It is well accepted by patients. Internal os is visualized
in 97-100% of cases.
16. Color doppler flow study
Prominent venous flow in the hypo-echoic areas near the cervix is consistent
with the diagnosis of placenta previa.
MRI
It is a non invasive method without any risk of ionizing radiation.
17. CLINICAL CONFIRMATION
• Double set up examination (vaginal examination)
• it is less frequently done these days.
Indications are
1. Inconclusive USG report
2. USG revealed type I placenta previa
3. USG facilities not available
18. Visualization of the placental implantation on the lower segment
can be confirmed during caesarean section.
Examination of the placenta following vaginal delivery reveals;
1. a tongue shaped, thin segment of placental tissue projecting
beyond the main placental mass with evidences of degeneration.
2. Rent on the membranes on the margin of the placenta.
3. Abnormal attachment of the cord.
21. COMPLICATIONS
During pregnancy
APH with varying degrees of shock
Malpresentation is common
Premature labour: either spontaneous or induced
During labour
Early rupture of membranes
Cord prolase
Slow dilatation of the cervix
Intrapartum haemorrhage
Increased incidence of operative interference
Post partum haemorrhage
Retained placenta
22. During puerperium
Sepsis is increased due to operative interference.
▫ Placental site near the vagina
▫Anemia and devitalized state of the patien
Subinvolution
Embolism
Fetal
Low birth weight
Asphyxia:Early separation of placenta,Compressionon of the placenta orCompression of the cord
Intrauterine death
Birth injuries
Congenital malformation
23. MANAGEMENT
1. Prevention
Adequate antenatal care.
Antenatal diagnosis of low lying placenta.
Significance of “ warning haemorrhage”.
Family planning and limitation of births.
2 .Management at home
The patient is immediately put to bed.
Assess the blood loss.
Quick but gentle abdominal examination.
Vaginal examination must not be done.
24. 3.Hospital treatment
Shift the patient to an equipped hospital
An intravenous dextrose saline drip.
Patient should be accompanied by 2/3 persons fit for donation of blood if necessary.
All cases of APH should be regarded as due to placenta previa unless proved otherwise
The bleeding may recur sooner or later
25. TREATMENT ON ADMISSION
Immediate attention
Amount of blood loss.
Blood samples are taken for grouping, cross matching and Hb.
A large bore IV cannula is sited and an infusion of normal saline is started.
Gentle abdominal palpation.
Inspection of the vulva.
Confirmation of diagnosis.
Formulation of line of treatment
Expectant management
Active management
26. EXPECTANT MANAGEMENT
Vital prerequisites
Availability of blood for transfusion
Facilities for caesarean section
Selection of cases
Mother is in good health status.(Hb >10 gm%, haematocrit >30%)
Duration of pregnancy is <37 weeks.
Active vaginal bleeding is absent.
Fetal well being is assured by USG.
27. CONDUCT OF EXPECTANT TREATMENT
Bed rest.
Investigations.
Periodic inspection.
Supplementary haematinics.
When the patient is allowed out of bed a gentle peculum examination is made to exclude local cervical
and vaginal lesions for bleeding.
Use of tocolytics and cervical encirclage are not helpful.
28. Expectant management is done in home
Patient lives close to hospital
24 hour transportation is available
Bed rest assured
Patient is well motivated to understand the risks
29. Termination of the expectant treatment
The expectant management is carried upto 37 weeks of pregnancy. By this time baby become mature.
Premature termination is done in conditions such as
Presence of brisk haemorrhage and which is continuing.
The fetus is dead.
The fetus is found congenitally malformed on investigation.
Steroid therapy
It is indicated when duration of pregnancy is <34 weeks. Betamethasone reduces the risk of respiratory
distress of the new born when preterm delivery is considered.
30. DELIVERY
Active management (Delivery)
Bleeding occurs at or after 37 weeks of pregnancy.
Patient is in labour
Patient in exsanguinated state on admission.
Bleeding is continuing and of moderate degree.
Baby with non reassuring cardiac status/ dead/congenitally deformed.
31. DEFINITIVE MANAGEMENT
Vaginal examination in OT followed by
Lower rupture of membranes or
Caesarean section
Caesarean section without internal examination
Contraindications of vaginal examination
Patient in exsanguinated state
Diagnosed cases of major degrees of placenta preavia confirmed by USG.
Associated complications like malpresentations, elderly primigravida, pregnancy with h/o previous
caesarean section, contracted pelvis etc
32. Low rupture of membranes
Low rupture of membrane is done using long Kocher’s forceps in lesser degrees of placenta previa (type
I & type II anterior).
Precautions during vaginal delivery
steps to restore the blood volume.
Methergine 0.2 mg.
Proper examination of the cervix should be done soon following delivery.
Baby’s blood Hb level is to be checked.