This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Social & Preventive Medicine
Denominator for calculating perinatal moality rate is: September 2009 
Select and explain. 
A. 1000 bihs, B. 1000 live bihs, C. 1000 still bihs, D. 1000 population
B: 1000 live bihs
Answer: B: 1000 live bihs 
Explanation: Ans. B: 1000 live bihs 164. Perinatal moality, defined as number of stillbihs (28 weeks of gestation and more) and deaths in the first week of life (early neonatal deaths) per 1,000 live bihs, is a useful additional indicator, and work is ongoing to improve estimates of stillbih rates, a major component of perinatal moality.