I can't find statistics on numbers of Canadian women who have babies over the age of 50 years. (I'm not surprised by this, maybe I should be?) The student has actually asked for statistics on postmenopausal women which have sought out IVF assistance.
CANSIM provides data for women up to age 49.
I am sharing an off-list suggestion with the rest of the dlilist as it may be of interest to others:
"The UN Statistics Division demographic yearbook historical supplement published in December of 1999, includes a table of live births to women over 50, for Canada, annually 1948-1995. http://unstats.un.org/unsd/demographic/products/dyb/dybhist.htm My guess (...) is that later issues of the DY will include later years: http://unstats.un.org/unsd/demographic/products/dyb/dyb2.htm"
I would also be happy to ask the division that publishes our vital statistics birth data firm if birth data for women over 49 is available as a custom product if you think that this could be of interest to your student. As you mentioned, these data don't seem to be available in our published products.