ahnie:
Op I think another factor responsible for birthing more kids are

A woman that has 3kids(girlies)would keep falling pregnant trying for a male chid for fear of being kicked out of her marriage.

Same goes for a woman that has male kids too

This depends on the husband 'cos last I checked women don't get pregnant on their own. Nothing stops a man who is struggling to fend for three children regardless of their gender to undergo a vasectomy. And what does he need another child for in the name of "I want a male or female child"?

The vast majority of Nigerians just like perpetuating poverty whenever and wherever they can: https://www.nairaland.com/6035550/nigerians-poverty-certain-acts-perpetuate