Just make sure you go back and take the last active pills before starting on the placebos. Your pregnancy protection depends on having 21 (or more!) days of active pills, and 7 (or fewer!) days without active pills. If you go into your placebo week on fewer than 21 active pills, it's possible that your ovaries will shake off the chemical hypnosis quickly enough to pop out an egg during the no-hormone week.

The M/T/W labels above a monophasic pill are really just there so that if you miss a day, you'll notice more quickly that you're taking your Tuesday pill on Wednesday, and you'll be able to take two pills that day to compensate.