It’s all about commitment, income and savings. The younger you marry, the higher the chance that you will get divorced. Younger parents also tend to be more irresponsible with their children, and there is a lot less of a safety net when you begin raising children early. Most people wait until they have a guaranteed stable income, are sure they wish to remain with their partner, and have enough of a backup incase anything goes wrong. This usually happens in your mid or early 30’s, and 20’s is usually considered too young.
That’s not to say it can’t work out, but you’re increasing your risk unnecessarily.