Contrary to what some were expecting following the release of the minutes of the Federal Reserve’s last major meeting, average mortgage rates edged further upwards last week, Freddie Mac said.

According to the results of Freddie Mac’s weekly survey, rates on 30-year fixed-rate mortgages went up from 3.62 percent to 3.66 percent, marking the fourth straight week the average rates had gone up.

15-year mortgages were up from 2.88 percent to 2.89 percent, a small increase but an increase nonetheless. Last month, the rates had fallen to as low as 3.49 percent for 30-year fixed-rate mortgages and 2.80 percent for the 15-year fixed option, both historical lows. These low rates have been responsible for driving a slow, yet steady improvement in the U.S. real estate market this year.

The current trend of low mortgage rates has been beneficial in several other ways, as home prices have gone up this year due to the increased demand and decreased supply. Builder confidence, according to the National Association of Home Builders, has reached its highest point since more than five years ago.

As a result, it is not unthinkable for the U.S. economy to make its first improvement in seven years by the end of 2012. Yet, both the housing market and the nation’s economy are still quite far away from what experts consider to be healthy levels of activity.

Also quite concerning, despite the low rates, is the difficulty many borrowers face in qualifying for the rates. However, recent government reforms, including recently announced changes in Fannie Mae and Freddie Mac qualifications for short sales, may improve the chances of a full-blown housing market recovery in time.