In large families, daughters see mothers pregnant all the time so they view pregnancy as a normative experience. Girls in large families grow up surrounded by children which makes them want to be mothers. Girls who grow up primarily w/children see pregnancy as highly conducive so they want to replicate this, having babies as their mothers did. Also, girls are pushed to parent younger/youngest siblings, so they see pregnancy at a young age as desirable, even the way to go!
Also in large families, there is no mention of contraception. In large families, contraception is seen as unnatural. The thought is that relations should result in children. The environment of large families also teach girls that their ONLY role is to be wives & mothers, nothing else. In large families, education for daughters aren't emphasized. Girls in large families are given the most rudimentary of education, college education isn't emphasized in such families.They are pushed to marry as soon as possible & to start having children. It is normal for girls in large families to marry in their teens, after they complete highs school. In certain cases, they don't even complete high school.
There are girls in large families who become pregnant because they weren't shown parental affection, love, & attention so they are susceptible to the first person(usually male) who shows them such attention, w/disastrous results.It is no accident that girls from large families tend to become pregnant as teenagers due to the abnormal, even negative factors of large family life: (1) seeing a constantly pregnant mother,(2) being surrounded by children, making them want children themselves,(3) having to constantly parent younger/youngest siblings,(4) being taught that their roles are only wives & mothers,(5) being PUSHED to marry & have children ear (6) higher education & careers never being stressed for girls, & (7) lack of parental affection, attention, & love. As I reiterated before, the large family is abnormal, even pathological in scope.
Children who grow up primarily among children absorb more backward, negative, & destructive characteristics. They are also more intellectually & socially immature. It is apparent in the large family environment as these girls are only exposed to children ad infinitum in their home environment, they don't see any alternative but to get pregnant. They aren't exposed to intellectual & cultural things to combat this.