Theory of obstetrics: An epidemiologic framework for justifying medically indicated early delivery

Table 2 Numbers and rates of perinatal death, live birth and small for gestational age (SGA) live birth among twin births, Canada (excluding Ontario), 1991 to 1997.

Note: Perinatal mortality includes stillbirths and neonatal deaths. Live births at each gestation served as the denominator for the conventional SGA rate and total births at each gestational week served as the denominator for conventional perinatal mortality rate. Under the fetuses at risk approach, birth, revealed SGA (R-SGA) and perinatal mortality rates were calculated using the number of fetuses at risk at that gestation as the denominator for the rate.
† Calculated by summing the number of fetuses who delivered at that and subsequent gestational weeks.
‡ All gestational ages, including those < 34 weeks and those with missing gestational age.

ISSN: 1471-2393