I joked a few times about families in the 70s and early 80s often having a 3rd child as a reserve here in Europe, since we grew up without child seats, airbags

I joked a few times about families in the 70s and early 80s often having a 3rd child as a reserve here in Europe, since we grew up without child seats, airbags and such things and the birth rate dropped by approximately 1 child per mother since these safety measures were introduced. Seems like there was some truth in that...