Birth control in the cosmer

[Rg2045]

So just something quick, who needs birth controle in the cosmer? Like for example scaa or at least scaa heritage seems to add the chance of getting pregnant whereas noble women had a higher chance of not being able to get pregnant. That of is course being part of TLR “Grand” design. 
then we look at roshar, and it’s not uncommon to hear some families with 4+ kids and others with just two even shallan and adolin don’t seem to be worried about having kids. But the entire world is constantly at war So we can assume that more kids are being born then on screen. 
And don’t get me started on the parshindi the way they reproduce makes no sense to me. 
 

I’m unsure how other planets work as I have only read mistborn and stormlight. 
but here’s my working theory. 
That places like roshar where the average person is more invested doesn’t have to worry about birth control as they can intend to have a child or not. Or it can be altered by someone who can see the SW like TLR. 
Whats your thought? WoB? 

[+Invocation]

A form of birth control was confirmed for Scadrial.

Spoiler

17th Shard

Are there forms of birth control on Scadrial?

Brandon Sanderson

Yes, there are. Witness, Vin and Elend not getting pregnant across several years.

17th Shard

Right. It's just not really mentioned in the books.

Brandon Sanderson

Yeah. I stay away from that intentionally. There are a lot of things I just didn't discuss due to the the feel of that book.

17th Shard Interview (Oct. 3, 2010)

Presumably there's something similar on Roshar, though I don't know if it would be affected by the higher Investiture limit on Roshar. If anything, I think that would make people more likely to carry to term, since it seems to be making them all significantly healthier than they would otherwise be. But who knows? Maybe the Alethi are all afflicted with heavy metal poisoning from all the warfare and that's keeping them down.

[Ookla the Silver]

I really doubt Brandon will ever talk that much about it.