Fertility Awareness Methods

The TwoDay Method

Average Failure Rate: 13.7%

The TwoDay method (or two-day method) of natural family planning has replaced the old cervical mucus method as the method of choice for a woman
who wants to predict fertility based on her body's signs.

The TwoDay method is a new fertility awareness technique developed at Georgetown University. To develop the method, researchers used data from the World Health Organization to determine the probability of pregnancy based on the presence or absence of vaginal secretions in a large sample of women. Researchers tested the technique with women in three different countries and found the TwoDay method to be safe and effective.

Effectiveness of the TwoDay Method

In research studies, the first-year pregnancy rate was 3.5% with perfect use. For couples who had intercourse during fertile days but used a back-up method, the method had a failure rate of 6.3%. The typical use failure rate of 13.7% includes all participants in the research study, whether or not the method was used properly.

How to Use the TwoDay Method

To use the TwoDay Method, women monitor themselves each day to determine whether or not they experience any secretions that day. However, unlike other methods that rely on this indicator, such as the ovulation mucus method or the sympto-thermal method, it does not involve analyzing the characteristics of the secretions (e.g., amount, color, consistency, slipperiness, stretchability, or viscosity).

The method rules are quite simple. A woman asks herself two questions: "Did I notice any secretions today?" and "Did I notice any secretions yesterday?"
If she noticed any secretions yesterday and today, she is potentially fertile. If she did not notice any secretions either yesterday or today (two consecutive days with no secretions), her probability of becoming pregnant is very low and it is safe to have intercourse that day. Couples using the TwoDay Method should avoid unprotected intercourse on days when the woman is potentially fertile.

For simplicity, women can note the presence or absence of cervical secretions at the same times each day. Checking after noon and just before going to bed at night is adequate for identifying fertile days, and also reduces the potential for confusing semen and cervical secretions.

Benefits of the TwoDay Method

The TwoDay Method of fertility awareness is easy to use, easy to teach, effective, and may fill a gap in needed services for the many women who currently are not protecting themselves from unwanted pregnancy. Unlike calendar-based methods or the Standard Days Method, the TwoDay Method is practical for women who may have unusually long cycles (over 32 days), unusually short cycles (under 26 days), or irregular cycles.
This method teaches women about their bodies and empowers them to work with their male partners to avoid unwanted pregnancies. This method uses no drugs or devices.

Limitations of the TwoDay Method

Women should first have a training session with a health care provider before using the TwoDay Method.
The TwoDay Method requires extra training for postpartum women, women who have recently used hormonal contraceptives, and perimenopausal women.
Like all natural methods, the TwoDay Method does not protect against sexually transmitted disease.

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