In Litvishe yeshivos, before the war, they only got married at about 40!
(I once heard from Rabbi Zecharia Gelley shlitoh in the name of a maggid, I forgot which one, that when he saw these people marrying at an old age, he said that he now understood why the mishneh says BEN shemoneh esre lechupa: when they could have had already a son (Ben) of 18, they themselves go to the Chupah!)