Is birth control pills, condoms, and a vasectomy a good combo of contraceptives to prevent pregnancy?

Contraception : Yes. All 3 of those together are very protective against pregnancy. Generally speaking, pregnancy would not be an issue after a male partner has obtained a vasectomy. This procedure would need reversal in order for pregnancy to occur. When used correctly birth control alone is 99.9% effective. Condoms are about 98% effective when used correctly.