Health care stocks and exchange traded funds have not been immune to the recent spate of market volatility. That much has been proven by health care ceding the top spot among all S&P 500 sector to utilities amid the recent pullback in stocks.

However, pockets of opportunity remain within the health care space, the S&P 500’s third-largest sector weight. One of those areas of opportunity is a seasonal trade with health care providers stocks, a trade that can be put on with one of the premier Obamacare ETFs, the iShares U.S. Healthcare Providers ETF (NYSEArca: IHF). [Health Care ETF Gets an Obamacare Boost]

According to the Stock Trader’s Almanac, late October marks the start of a favorable seasonal period for shares of health care providers, a group that includes Aetna (NYSE: AET), Cigna (NYSE: CI) and Dow component UnitedHealth (NYSE: UNH). Those stocks combine for nearly 25% of IHF’s weight.

This is a seasonal trade with some legs, too. As the Stock Trader’s Almanac notes, favorable seasonality for health care providers can last from late October through mid-May. From Oct. 31, 2013 through May 15, 2014, IHF gained 4.1%, more than double the 1.9% gained by the S&P 500 over the same period.

With health care mergers and acquisitions activity picking up, IHF could find itself in the spotlight even more. Earlier this year, Morgan Stanley identified Express Scripts (NasdaqGS: ESRX), WellPoint (NYSE: WLP), Cigna and Aetna as possible takeover targets. Those stock combine for over 30% of IHF’s weight. Those are four of IHF’s top-five holdings and combine for 27% of the ETF’s weight.

To be fair, IHF, like other health care ETFs, has pulled back in recent weeks. The ETF is down 4% over the past month and investors have pulled $82.1 million from the ETF this month.