T.F.
When my hubs got a snip snip I stayed on the pill to ensure no oopsie until I had a complete hysterectomy and only then was I 100% sure.
If your hubby had the snip snip, he MUST be checked regularly for several months to ensure there are no swimmers left in his system. It took my hubs 6 months to reach that point and I STILL stayed on the pill just in case.
I do not recall any adverse effects when I went off the pill 4 months before I tried to conceive and then again shortly before my surgery.