Would this idea help address declining populations in many countries?

How about offering cheaper healthcare, cheaper child care, sensible maternity/paternity leave/benefits, not tying healthcare to jobs, providing better work life balance, better wages... and on and on?

Babies are not like buying clothing, that you try it on for a few days and return if you don't like. Primary reason most people don't have more kids is the economic stress and affordability. Of course there are people who genuinely do not want children, no matter how much they earn. Those are the minority though.

And yes, not all countries face all problems listed above, it is just a collection of problems that countries face at different levels. But in general, social safety nets are disappearing everywhere. We can't expect responsible people to have more kids in this situation. Of course irresponsible/gullible people will still have kids even if they can't afford, which will only add to the problems

This is a topic near and dear to my heart, I have a startup I’m bootstrapping to pay people who don’t want kids to not have them. “We buy unwanted fertility.” This covers their out of pocket costs for the healthcare needed to affirm their reproductive choice.

The data is robust that some don’t want children out of economic reasons, and others don’t want them out of lifestyle choices (prioritizing self over a thankless job). Across several national pro natalist policy programs, the evidence shows that even when enormous amounts of benefits are provided, it barely moves the realized fertility outcome.

(40% of pregnancies in the US and internationally, annually, are unintentional, and we have enough humans we don’t take care of already [1], we should be radically empowering as many as people who don’t want to have kids to not have them)

[1] https://news.ycombinator.com/item?id=44407283

Is it to much to ask for to plan and imagine if something works for you before you get it? Or is it so hard to imagine that people actually know what they want or don't?

This sounds just like some people approach pets

I think finances are more a concern/incentive.

Consider: the government pays a salary to each married family while they raise children; the salary would be equivalent to a blue-collar job, and it would scale with the number of children up to a point (e.g. 4 kids).

I strongly believe that'd lead to many more marriages and childbirths. Many people not interested in raising kids would prefer it over a "regular" job. Families with adoptive children would also be paid, so it could decrease adoption difficulty and stigma as a side-effect.

However, some people will game this policy, and it would be very expensive to implement.

That's one way to think about numbers and not about the persons.

I believe most of countries have orphanages already -- and what you're suggesting already exists in some countries (I do believe we still have that in Brazil).

While that could increase the number of people, orphanages are not great places to raise a child (with rare exceptions). Imagine you growing up with a large group of other child, and nobody actually take the time to take care of you. What kind of person would you be today?

Currently every state has a safe haven law where new mothers can leave an unharmed infant up to 7-30 days depending on the state anonymously at hospitals, fire stations or police stations and it’s not considered abandonment.

Finding people willing to adopt newborns is also fairly easy now.

pregnancy is no joke, you don’t undergo that experience just to see if you like having a baby for one year

The single most effective idea is tax reduction proportional to number of children in the family.

Yet nobody cares in the west to implement even this. Having children became a luxury.

This is a problem not solved by a startup.