ABSTRACT
The incidence of twins continues to increase worldwide1 despite the recent modest success in reducing the incidence of higher-order multiples2,3. Among these latter gestations, many are reduced to twins, whose numbers continue to augment those that occur as a result of a maternal cohort who choose to conceive at later ages4. The end result of these diverse circumstances is reflected at the author’s hospital, a university center in Toronto, Canada, where 6% of all deliveries were twins in 2001-02, compared with 2.3% just 4 years ago.
