CycleBeads® and iCycleBeads apps are based on a natural family planning method called the Standard Days Method®. This method was developed by the Institute for Reproductive Health at Georgetown University to fulfill the need for an effective, easy to use, natural birth control option. It is designed for women with cycles between 26 and 32 days long.

Research Proven Effectiveness of the Standard Days Method

In efficacy studies conducted in several countries, researchers found that when used correctly the Standard Days Method is more than 95% effective in helping women avoid pregnancy . This means that fewer than 5 of every 100 women who keep track of their cycle days and do not have unprotected intercourse on Days 8 through 19 of their cycles became pregnant during the first year of using the Standard Days Method.

The research also found that women who do not keep careful track of their cycle days or have unprotected intercourse on Days 8 through 19 of their cycles, are much more likely to get pregnant. When women sometimes used the method correctly, but sometimes had unprotected intercourse on Days 8 through 19, 12 out of 100 got pregnant during their first year of use. This means that in "typical use" the method’s effectiveness is approximately 88%.

To read the original research article, click here: Efficacy of a New Method of Family Planning: The Standard Days Method.

Based on this research, CycleBeads compares favorably to other contraceptive options both in Correct Use effectiveness and Typical Use effectiveness.


The Scientific Basis for the Standard Days Method

The Standard Days Method is based on reproductive physiology. A woman's fertile window (the days in the menstrual cycle when she can get pregnant) begins approximately five days prior to ovulation and lasts up to 24 hours after ovulation. This is because sperm remain viable in a woman’s reproductive tract for up to five days, and the ovum can be fertilized for up to 24 hours following ovulation. Therefore, a woman's fertile window is approximately 6 days long per cycle.

However, during any given cycle a woman’s potential fertile days can vary due to the fact that the exact timing of ovulation can vary from one cycle to the next. Most ovulations occur around the mid-point of the menstrual cycle (+/- 3 days).

Researchers at the Institute for Reproductive Health identified the potential fertile window in a woman’s menstrual cycle during any given cycle using a computer simulation that took into account the probability of pregnancy, probability of ovulation occurring on different cycle days, and variability in cycle length from woman to woman and from cycle to cycle. Their analysis found that avoiding unprotected sex on days 8 through 19 of the cycle provided maximum protection from pregnancy while minimizing the number of days to avoid unprotected intercourse.

Women with menstrual cycles between 26 and 32 days long can use CycleBeads and the Standard Days Method to prevent pregnancy by avoiding unprotected intercourse during the 12 fertile days identified by the method.

Implications for Using this Natural Family Planning Option

If a woman doesn't want to get pregnant, she should use a back-up method of birth control or not have sex on Days 8 through 19 of her menstrual cycle. On the other hand, if a woman does want to get pregnant, these are the days when pregnancy is most likely. Patented tools based on this family planning method help a woman use this method correctly and effectively. See CycleBeads, iCycleBeads Smartphone Apps, and CycleBeads Online.

1. Arevalo M. et al., Contraception, 2002;65;333-338.
2. Wilcox AJ, Weinberg CR, Baird DD. Post-ovulatory ageing of the human oocyte and embryo failure. Human Reproduction, 1998;13(2):394-397.