Many studies in women have looked at the possible link between talcum powder and cancer of the ovary. Findings have been mixed, with some studies reporting a slightly increased risk and some reporting no increase. Many case-control studies have found a small increase in risk. But these types of studies can be biased because they often rely on a person’s memory of talc use many years earlier. One prospective cohort study, which would not have the same type of potential bias, has not found an increased risk. A second found a modest increase in risk of one type of ovarian cancer.
There are resources available to you if you need them, though. Also, don't discount cloth diapers if you have the means to launder them. They're often easier to get at free or reduced cost, not to mention they're way better for the environment, and you can be super smug about that. (Unrelated, but once you're done diapering your baby, those diapers really make the best dusting cloths and glass cleaners.)
There are several different organizations around the country that distribute free diapers to needy and low income families. Many of these are charities or churches, with some government programs also assisting. There are programs for single mothers, teenage moms, and families living in poverty. Anyone that needs free or low cost diapers near where they live, and that meets qualifications, may apply.