APPALLINGLY belated reply on my part, haha, but, thank you for these! the book rec & the paper both look fascinating, and i don't think i even thought of birth control way back when i first was toying with this question, but—yeah, that makes sense as a hugely impactful thing. (definitely one of those things i came to realize more & more when i read more history stuff as an adult—easy to overlook since i've very-fortunately been able to take it for granted my whole life, but that's SO far from the norm, historically speaking...!)