Is Calendar Method Effective

Is Calendar Method Effective. Days 8 through 19 of every cycle are considered fertile days for all users of the standard days method. How effective is the rhythm method for birth control?

The rhythm method, also called the calendar method or the calendar rhythm method, is a form of natural family planning. There are limited studies into the effectiveness of the rhythm method specifically, but the standard days method is shown to be 88% effective with typical use.