Lately I’ve been noticing that the people who mainly should not have children, whether due to economic limitations, illnesses, or even mental instability, are the ones who have the most children, and many times they end up as single fathers/mothers. My question is whether it would be a good idea to implement some kind of regulation and set minimum requirements that must be met, mainly to prevent the child from ending up in the future as a criminal or a social burden due to those factors.


Regulations will be broken, and the people who break them will only be in more peril. There are many cases of parents killing their firstborn in China, if the child was female because they were only allowed one child and men are deemed more important.
The factors you list (low economic status, mental instability, illness) are not hard factors. They can be addressed and I feel the state should focus on that by supporting parents financially, make sure there is affordable housing, medication and food, boost especially women’s financial independence, reduce wait times for health specialists such as psychologist.