Placenta Praevia - APH

Question 1

Define Placenta praevia ?

Answer 1

Abnormal location of the placenta at or near the internal cervical OS.

Question 2

What are the RISK FACTOR of placenta praevia ?

Answer 2

1. History of placenta praevia ( 4-8% recurrence risk ) .
2. Muliparity .
3. Increased maternal age .
4. Multiple pregnancy.
5. Uterine tumour ( e.g Fibroids ) or other uterine anomalies
6. Uterine scar due :

A. Previous abortion 
B. Caesarean section
C. Dilation.
D. Dilation and 
E. curettage or myomectomy  

7. ” Dropping down “ theory of zygote and its implantation in the lower uterine segment (LUS) which normally implants in the upper segment – This could be as result of poor decidual reaction in the upper uterine segment.
8. Smoking and drug abuse (Cocaine ) increase the incidence of placenta praevia - During smoking there is carbon monoxide production leading to tissue hypoxia causing compensatory placental hypertrophy which gradually happen at the lower uterine segment .

Question 3

What are the CAUSES of haemorrhage ?

Answer 3

The inelastic placenta get detached from the progressively thinning and dilating lower uterine segment during the last trimester of pregnancy and in labour and thereby bleeding occurs from the opened maternal sinuses.

The blood lost is almost always maternal in origin , but in traumatic separation of the placenta , foetal blood may escape from torn villi.

Question 4

What are the presentation of a patient with Placenta praevia ?

Answer 4

1. Recurrent , painless bright red vaginal bleeding :
   A. Onset of bleeding depends on degree of praevia (i.e. Complete bleed earlier ) .
   B. Initially , bleeding may be minimal and cease spontaneously but can be worse later on.
   C. Bleeding at onset of labour can occur with marginal placenta praevia.
2. Uterus is soft and non-tender.
3. Presenting part high or displaced

Question 5

What are the physical Examination that can be performed in a patient with Placenta Praevia ?

Answer 5

General examination:

1. Pallor is propotionate to the visible blood loss .
2. The patient may or may not be in shock depending on the amount.

A.The Abdomen is soft
B.The Uterus is relaxed non-tender, corresponding to the period of amenorrhoea.
C. Malpresentation are often associted .
D fetal parts are easily palpable and FHS may be normal.
C. Stalworthy’s sign