Not typically - even though that's a popular sales pitch by insurance agents. One of the big advantages of an annuity is that your money grows tax-deferred. But you already get that tax-deferral through the IRA, so there's no advantage to holding an annuity over a regular mutual fund.
In fact, a variable annuity is usually a terribly expensive way to fund an IRA. An annuity may offer insurance provisions, such as a death benefit for your beneficiary. But in most cases you'll be better off sticking with low-cost IRA investments and using the money you save to purchase a term life insurance policy.