No I am saying that under the social system in which marriage was formalized it was expected that people would have kids because there was no birth control and

No I am saying that under the social system in which marriage was formalized it was expected that people would have kids because there was no birth control and people like to have sex, kids were pretty much assumed as a general byproduct of marriage. And for the vast majority of the couples it was true so the barren were rounding error and were not considered as a separate case.