Which denominator and multiplier does the maternal mortality rate use?

1. The numerator counts deaths from causes related to or aggravated by pregnancy, up to 42 days after a pregnancy ends. 2. The denominator is the number of live births reported in the same period, which is why the measure is really a ratio. 3. The result is conventionally expressed per 100,000 live births. 4. Per 1,000 live births is the convention for infant, neonatal and postneonatal rates, not maternal deaths. 5. A mid-interval population denominator would make this an ordinary cause-specific mortality rate instead. _Source: CDC Principles of Epidemiology in Public Health Practice (3rd ed., US federal, public domain), Lesson 3 "Measures of Risk", section Maternal mortality rate_