I had my DS at 15/16. I'm 23 now.
It was hard.
When I was pregnant with him, I was very sad. I wanted him to have the very best in life. Was in a shitty relationship with his dad, I couldn't afford the "nice" stuff that I would of loved to of bought for him. Materialistic stuff isn't important, and I knew that, but I didn't want to have to worry about money, struggling, I wanted to give my DS the best of everything.
I knew the only way to get out of this shit hole was to carry on through with my education and to leave the abusive dad behind. When DS was 8 weeks, I went back to my mainstream school to complete my GCSE's, straight after A levels, after that I got my Bachelors. Two days ago, I received news that I got accepted into the Master course that I applied for (I'm not too sure if I'll do the course to be honest). During all if this, I was being abused, had to deal with the emotional turmoil that my DS has special needs and attending various appointments.
Let's just say, life wasn't easy. I am in a better place now, I have a good job (though it's part time), DS is developing really well and is at a fantastic specialist school and I ditch the dead weight of his father.
So, I have to stick two fingers up to this comment "Or they went onto Oxbridge and became a physicist and are now on £99K a year. Sorry, but I don't believe any of this. Many people who DON'T have a baby in their mid teens don't achieve this, so I am damn sure a teen mum wouldn't. Only in the movies!!!".
It's interesting you say this "the baby, and is massively dependent on their parents (or other more mature adults.)". I've spoken to many adult parents who heavily rely on their parents to look after their kids. I bet they don't get much stick.
Back to the OP's question. Would I judge a pregnant 14 year old ? No I wouldn't, I would offer advice and support.
Plus, a few of my family member were persuading me to have an abortion. At that time, all I thought was "No fucking way". Looking back then, if I went through an abortion, it would of fucked me up mentally.