Teen Pregnancy's tropeworthiness

This trope seems to be People Sit on Chairs, as all it's defined as is "character conceives child before they turn 20". But can it be divided into tropeworthy conventions?

The examples under Teen Pregnancy seem to fall into two tropes:

• A subplot or plot features a teen parent in conflict with or adapting to this fate, pre- or post-birth.
• Throwaway teen pregnancies used as a device in establishing either a character's backstory or setting (e.g. character is adopted to cover up their mom's teen pregnancy, societal underdevelopment in times or places being correlated with teen pregnancies, etc.).

Edited by Albert3105 on May 11th 2021 at 1:27:51 PM

A teen pregnancy has a huge impact on the character's life, and thus the plot if the character is important. Not sure how that's not a trope. In 20th century and later settings, there's a big taboo against it.

And both of the concepts you just mentioned effectively stem from conflict around that same taboo. The difference is just whether the focus is on the parent or not.