CLINICAL FEATURES OF PLACENTA PRAEVIA, Bleeding, Pain, Provoking factor,

 

CLINICAL FEATURES OF PLACENTA PRAEVIA

a.     Bleeding.

Bleeding in placenta praevia is characteristically bright red in colour and is true representative of the actual amount of haemorrhage. Heavy vaginal bleeding classically occurs in the earlier part of third trimester when the lower uterine segment elongates rapidly. This haemorrhage is often preceded by small episodes of bleeding in early pregnancy associated with slow elongation of the isthmus. It is less common for the placenta praevia to bleed for the first time after 36 weeks and is rare after 40 weeks. The first haemorrhage in placenta praevia is often relatively small in amount measuring about 120 ml in 50% of the cases and is called warning haemorrhage. Bleeding in placenta praevia is usually recurrent and every subsequent episode is heavier than the previous one.

b.    Pain.

Pain is not a feature of placenta praevia and bleeding from placenta praevia is typically described as painless.

c.      . Provoking factor.

The bleeding is usually unprovoked and the woman often notices wetness in the undergarments as a first symptom and is alarmed to discover that she is bleeding. In some cases the bleeding may be initiated by sexual intercourse, pelvic examination or Braxton Hick’s contractions.

d.     Shock.

 Shock in case of placenta praevia is not as pronounced as is the case with placental abruption because the patients tend to present early due to revealed nature of haemorrhage and the contribution of pain to shock is lacking.

e.     Asymptomatic.

One third of all women with Placenta praevia never bleed antenatally, and before the wide spread use of ultrasound such cases used to remain undiagnosed until the onset of labour. These cases are now usually picked up on routine ultrasound and pose special management problems.

f.        General physical examination.

The patient looks anxious but not distressed and the degree of pallor varies with the amount of blood loss. The blood pressure is generally maintained by compensatory mechanisms unless the haemorrhage is very severe, when the patient may present with shock.

g.     Abdominal examination.

In contrast to placental abruption the fundal height corresponds with the duration of gestation in placenta praevia.Uterus is soft and allows an easy palpation of the fetal parts. Fetal malpresentation is more common and fetal heart sounds are easily audible. A judgment of type of placenta praevia can be made on abdominal examination as the presenting part will be held high by a central, pushed to one side by lateral, pushed forward over the pubic symphysis by posterior and rendered difficult to palpate by the anterior placenta praevia. A deeply engaged head always suggests that placenta praevia if present is of minor degree.

h.      Pelvic examination.

 Both speculum and digital pelvic examinations can exacerbate the bleeding from placenta praevia. It is therefore very strongly recommended that pelvic examination of any kind must never be performed in all cases of antepartum haemorrhage until after the placental site is localized by ultrasonogram.