Much of the past decade for the stock market could be summarized in one punctuation mark -- an exclamation point. But so far in 2022, the better choice would be a question mark. There's considerable uncertainty about the overall economy and how it will impact stocks.

Because of this uneasiness, it's understandable why many investors would be reluctant to dive in right now. However, there are options that shouldn't cause too much angst. Here are three high-yield dividend stocks to buy in September without any hesitation.

1. Easterly Government Properties

Why are the rectangular pieces of paper in your wallet with former presidents and other notable leaders printed on them worth anything? They're backed by the full faith and credit of the U.S. government. Easterly Government Properties (DEA 1.19%) can make the same claim about most of its leases.

Easterly is a real estate investment trust (REIT) that, as its name suggests, owns government properties. All but one of the company's 94 properties are leased to U.S. government agencies. Easterly especially focuses on critical federal agencies that are growing. 

All REITs must return at least 90% of their taxable income to shareholders in the form of dividends. Easterly's dividend yield currently stands at 5.76%.

Sure, the stock is down this year -- mainly due to investors' worries about rising interest rates. However, Easterly believes that some of its rivals are overextended while its financial status remains strong. This could position the company well for picking up attractive properties over the next couple of years. 

2. Enterprise Products Partners

Energy ranks as one of the best-performing sectors so far in 2022. Multiple factors are serving as tailwinds, notably Russia's invasion of Ukraine earlier this year. Midstream energy company Enterprise Products Partners (EPD 1.09%) has been one of the winners, with its stock jumping more than 20%.

Enterprise's dividend yield tops 7%. The company has increased its distribution for 24 consecutive years. The distribution has grown by a compound annual growth rate of close to 7% during that period. 

Higher commodity prices don't benefit Enterprise as much as they do many energy companies. Enterprise doesn't base its pipeline and processing fees on oil and gas prices. However, the current market dynamics boost demand for crude oil, natural gas, natural gas liquids, and petrochemicals that flow through the company's pipelines.

What about Enterprise's prospects beyond the next year or two? Co-CEO Jim Teague stated in the company's second-quarter conference call, "Oil and gas will be in high demand for decades." He's almost certainly right, which should bode well for Enterprise's long-term fortunes. 

3. Medical Properties Trust

Like Easterly Government Properties, Medical Properties Trust (MPW 4.04%) (MPT) is a REIT. Also like Easterly,  MPT has seen its stock fall quite a bit so far this year.

But while MPT's leases aren't backed by Uncle Sam, they're still quite secure. The company owns hospital properties in 10 countries. Even if one of MPT's tenants experienced financial issues, its properties would probably be highly attractive to other hospital operators due to their locations.

MPT's dividend yield of 7.7% ranks as the highest of these three stocks. The company also has the lowest dividend payout ratio of the group (57%), which indicates an ability to easily fund the dividend with earnings.

The potential for higher interest rates could weigh on MPT's share price over the near term. However, the healthcare REIT should have excellent opportunities to grow over the long term. And with shares trading at only 8.2 times expected earnings, MPT appears to be a bargain right now.