TwoDay method

The TwoDay method is similar to the cervical mucus method, but it was devised to simplify the process of determining fertile days by only monitoring the presence — not the quality — of cervical mucus.

Effectiveness rate. The typical effectiveness rate among those using the TwoDay method is 86 percent. In other words, out of 100 women using the TwoDay method over one year, 14 will get pregnant.

Side effects and health risks. As with the cervical mucus method, the most significant disadvantage of the TwoDay method is prolonged periods of abstinence or the use of barrier methods. This method doesn't protect against STDs.

How to use the TwoDay method. If you decide to use the TwoDay method, check for cervical mucus at the vulva or on toilet paper two times each day: once in the afternoon, and once before bed. Ask yourself two questions. Do I have any secretions today? Did I have any secretions yesterday? If the answer to either of these questions is yes, then you should avoid unprotected intercourse, because you might be fertile. If the answer to both questions is no, then you're not in a fertile part of your cycle and can have unprotected intercourse.

Many women use a chart to mark fertile and infertile days, as well as the start of each cycle. It's important for women using this method to know how to recognize cervical mucus.

Cost and availability. Using the TwoDay method costs nothing, but classes that teach this technique may charge fees, which vary from region to region.