I think it in the novel of Journey to Sorrow's End where Clearbrook says she feels a stillness within herself, and doesn't think she will have more chldren. Bearclaw was pretty old for a Wolfrider when he recognised Joyleaf though.
Well, maybe reproduction is easier to males than females. Although, it makes me wonder... How old Joyleaf was when she gave birth to Cutter?
And yeah, I had completely forgotten Tyldak, although the whole tribe of the Gliders had difficulties to reproduce, because they did not get hurt or die. And considering really old elves like Savah and Ekuar, I just guess they are so old and experienced that it is hard to find a soul to match, or so?
As I think of it, Woodlock and Rainsong had their children within a short period. But then again, Moonshade and Strongbow had three kids as well, but within a longer period.