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Standard Days Method


Updated August 09, 2011

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Standard Days Method

CycleBeads for the Standard Days Method

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Natural family planning methods can be effective contraception when used correctly. Research demonstrates that the Standard Days Method can meet the needs of a variety of women with varying characteristics and circumstances. The Standard Days Method, a fertility awareness birth control method, was developed by researchers who determined a formula that balances the need to provide effective protection from unplanned pregnancy while restricting a woman’s fertile period to as few days as possible.

To be effective, couples must recognize the importance of tracking cycle length and abstaining (or using condoms) during fertile days. Of all the natural family planning options, the Standard Days Method requires the least days of abstinence or barrier contraception. To successfully use this method, all you have to do is avoid unprotected sex from day 8 through day 19 of your cycle (a total of 12 days).

To maximize Standard Days Method effectiveness, women can use CycleBeads. These consist of a circular string of 32 color-coded beads. Using CycleBeads is simple -- you move a rubber ring over one bead every day as a way to visibly track where you are in your cycle. The colors of the beads show whether you are on a fertile or infertile day. CycleBeads are also a great way to monitor your cycle lengths to make sure they are between 26 and 32 days.

To learn more about this method, I researched an article on UpToDate -- a trusted electronic reference used by many doctors and patients. According to UpToDate,

“The Standard Days Method (SDM) determines fertile days using two sets of probabilities: the probability of pregnancy with respect to ovulation and the probability of correctly timing ovulation with respect to the mid-point of the cycle. The SDM is appropriate for women whose menstrual cycles are usually between 26 and 32 days (approximately 78 percent of cycles are within this range). Thus, women with polycystic ovary syndrome, adolescents, breastfeeding women with amenorrhea, women who are recently postpartum, and women in the menopausal transition often are not good candidates.

A clinical trial in which nearly 500 women were taught this method and followed prospectively for up to 13 cycles reported a pregnancy rate of <5 per 100 women per year with correct use. The typical user pregnancy rate of the SDM was 12 per 100 women per year."

Basically, the Standard Days Method works off of the premise of that abstaining from sexual intercourse during your fertile days will significantly decrease your chances of becoming pregnant. SDM calculates your fertile days by considering when you are most likely to ovulate. Because it is one of the easiest of all fertility awareness methods to use, most women can successfully use this method. As long as your menstrual cycle is 26 to 32 days long, you are a good candidate for the Standard Days Method.

Because teenagers' cycles are typically not regular, the SDM may not be ideal for them. If you have certain issues that cause irregular periods, like just having had a baby, beginning menopause or skipping/having no period, the Standard Days Method will not be reliable. Additionally, SDM is not a good option if you have polycystic ovary syndrome (an imbalance of a woman's female sex hormones, which can cause changes and irregularities in the menstrual cycle).

That being said, research shows that the Standard Days Method can be very effective at preventing pregnancy. One study found SDM to be over 95% effective (less than 5 out of every 100 women who correctly used SDM for over a year became pregnant). Yet not all women will use this method correctly, so with typical use, this method is about 88% effective (approximately 12 out of every 100 women using this method for one year became pregnant).

The leading reason for SDM failure was that couples knowingly took the risk of having unprotected sex on fertile days. You also need to monitor your cycle length since you may have less regular cycles than you actually first thought. The Standard Days Method will be less effective if you have frequent cycles outside of the 26- to 32-day range. So if in one year, you have more than one cycle that is longer than 32 days or shorter than 26 days, it would be wise to find a different contraceptive method.

Additional data that included a total of 1,646 diverse women from 14 pilot studies also shows promising results. Results reveal that the Standard Days Method is an accepted option for women who did not want to use any type of birth control device. Another important finding was that the SDM allows for increased male involvement as it encourages men to abstain or use condoms during fertile days, obtain condoms and help their partners keep track of fertile days. It seems that the Standard Days Method improved patient-doctor interactions because doctors can use these discussions to screen for issues that undermine successful use, like poor couple communication, alcohol use and partner violence. Additionally, because this method relies on strong couple communication, couples who are considering its use have the opportunity to explore their relationship and deepen their connection to one another.

A doctor can help you determine if the Standard Days Method is appropriate through some simple counseling. Research suggests that a doctor only needs to ask about period regularity. If your periods typically are about a month apart and generally come when you expect them, a doctor should consider counseling you about this method. You can begin using the Standard Days Method if you know when your last period started -– if not, you will need to wait until your next period.

Surveys and research consistently reveal that women choose fertility awareness methods, like the Standard Days Method, because of concerns about side effects and health risks of other birth control methods, such as hormonal contraception. A lot of women do not consider natural methods due to lack of information, misguided beliefs about these methods being inconvenient, and/or concerns about failure rates. According to UptoDate, only 1% of women in the U.S. use fertility awareness methods and 3.6% use it worldwide.

So, if you are looking for a fertility awareness birth control method, keep in mind that the Standard Days Method appeals to a broad range of women throughout the world. It is the easiest of all natural methods to both teach and use, and men and women report high satisfaction levels with this method.

Want to learn more? See UpToDate's topic, "Fertility awareness-based methods of pregnancy prevention," for additional in-depth medical information on the Standard Days Method and other fertility awareness options.

  • CycleBeads: Compare Prices


Jennings, Victoria. "Fertility awareness-based methods of pregnancy prevention." UpToDate. Accessed: July 2011.

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