When it comes to flight connections, the rule of thumb is: Don't do it. But when the lure of a cheap ticket with a connection is too much to resist, choose wisely.

A new survey of travel agents by Travel Leaders Group -- one of North America's largest travel companies -- found that when it came to connections, the No. 1 airport clients wanted to avoid was Chicago O'Hare. More than 56 percent of respondents said they tried to avoid the Midwest hub.

Respondents could choose up to three different airports when asked the question, "If your clients are flying and need to connect through a hub airport, which hub do they try to avoid?"

Coming in as the second-to-least favorite? Another major hub: New York's John F. Kennedy International Airport. The other New York-area airports didn't fare much better. After Atlanta, which came in third, came New York's LaGuardia and New Jersey's Newark Liberty International, in fourth and fifth places, respectively.

The top 10 worst airports for flight connections, according to Travel Leaders Group:

1. Chicago O'Hare

2. New York's JFK

3. Atlanta's Hartsfield-Jackson International

4. New York's LaGuardia

5. Newark Liberty International

6. Miami International

7. Denver International

8. Philadelphia International

9. Dallas/Fort Worth International

10. LAX-Los Angeles International Airport