The stereotype of the mom getting pregnant

Does anyone else hate the stereotype of the mom getting pregnant when they already have like three kids in their teens? First of all, it's unrealistic that all these early to mid 40s women are having a baby. And second, at this point it just feels like lazy writing to add conflict. Whenever I'm watching a show and the mom gets pregnant I just roll my eyes. It's ridiculous how many shows use this just to add tension. And why do the parents always keep it a secret until one of the kids already finds out. I know most couples wait 3 months before telling people but these parents are telling these teenage kids when they're like 6 months pregnant LIKE JUST TELL YOUR KIDS!?

Anyway, please tell me I'm not alone in hating this.