no, most important factors are wealth(lack of it), cheap housing in ok areas that can accommodate 1-2 children (lack of it, good social security (parental leave(adapted just recently to be better), free/cheap healthcare for mothers during pregnancy + for children, etc...) and proper infrastructure (walkable neighborhoods, play fields, cheap childcare, etc...).

Some say that it's not possible and it's just what happens in developed nations, but if you look closely to the stats, you'll find out that for eg. in sweeden, the birthrates increase to >=2 when families reach certain income lvl.

Others say that we must become poor again to increase brates, but I don't think it's that simple, if we look closely at different countries, basically brates are high when having more children increases the wealth/quality of life (v poor countries) or where having more children doesn't impact current lifestyle that much (if you have money you can afford nannies/childcare/school/bigger apt). Where it drops is when ppl achieved some lvl of wealth/good qol but it will be heavily impacted by having a child, aka the middle class.