Apples and oranges. Abstinence assures one of no wanted, unwanted, unexpected, or inconvenient passengers on board.
Any husband who does not wish to assume any risk whatsoever of an unwanted pregancy but does not wish to forego sex--and what normal husband would?--can 100% assure pregnancy won't happen with a quick and common little medical procedure.
Ditto for any woman.
Otherwise they should be aware that every now and then a new person is clever enough to make it past the best defenses to thwart him/her. I know because I gave birth to two little bundles of joy who made it past the best known defenses of that day. Both times I was not a happy camper when I found out I was pregant. But I sure can't imagine a world without them now.
(P.S. Welcome back, Intrepid. I missed you.

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