According to ICMR the most common cause of infant mortalilty is –
The most common causes of Infant death are :

Prematurity & low birth weight (51%)
Acute respiratory infection (17%)
Diarrheal diseases (4%)
Congenital malformations (5%)
Birth injuries (3%)
Cord infection (2%)
Prematurity
Diarrhoea) diseases
Congenital anomalies
Acute repiratory infection