From AIA IPO Prospectus:
Low interest environment for the last decade created by the US -- to be specific by Greenspan and Bernanke, reduce the return of insurance companies' investment.
Yields on fixed income securities are highly related to interest rates, lower interest rates would result in lower yields for fixed income securities. As insurance companies invest most of its money in fixed income securities -- for example, AIA has 90% of its investment in fixed income securities -- lower yields received by insurance companies reduce their profit. This directly limit their ability to pay policy holders dividend, such as the non guaranteed dividends.
Not a good idea to use insurance policies for saving under low interest rate environment.