Getting married at a young age won't make you poor.Having kids at a young age will make you poor for sure.
I don't know about your country,but rising a kid from it's birth to the age of 18 costs more than 150,000 USD in the USA.The cost might be lower in the other countries,but it's still a significant amount of money.
I agree. Look at those countries that has policy regarding child birth control they are now highly developed just like China or any other countries. Marriage at young age in my opinion can be good or not in terms of economic status. Raising kids is not a joke most especially if we are living in the lower status in the society as money could be hard to find if the parents are unemployed it will only cause problems to the family and country.