This paper examines Canadian trends and patterns in multiple births in relation to total confinements, singleton births, maternal age, parity, gestational age and birth weight using vital statistics from 1974 to 1990. Multiple-birth rates in Canada increased from 912.8 to 1,058.9 per 100,000 confinements between 1974 and 1990. The increase is especially noticeable for women over 30. The rate of triplet and higher-order births increased from 8.3 to 21.7 per 100,000 confinements between 1974 and 1990. The proportion of multiple-birth babies that were pre-term (