When MTV came out with their show, 16 & Pregnant, the point was to try and show young girls the struggles of teen pregnancy and the importance of birth control or abstinence. Each episode followed a different girl from when she finds out she's pregnant until a month or so after the birth. Most teens chose to keep their baby, while others chose to give their newborn up for adoption.
The episodes were supposed to be one-offs, but it became evident that the show was more popular than anyone anticipated. This prompted the network to change up their strategy, which is when Teen Mom came to fruition. MTV picked four girls from 16 & Pregnant to be part of a reality series that would follow their struggles as teen parents. Amber, Farrah, Maci, and Catelynn were thrust into the spotlight and became instant celebrities.
The girls started out pretty average, struggling to finish school and care for a newborn, all under the age of 18. But as seasons went on, people started to notice something: these girls weren't struggling at all. Sure, they were still parents. But their cars got nicer, their houses got bigger, and their appearance was more glamorous.
But once you see their salaries, it's not hard to understand why they can afford these luxuries.