• 97-98% effective with perfect and use; less than one out of every 100 women will become pregnant each year
• 80% effective with typical use; 20 out of every 100 women will become pregnant each year

Additional Sources for Effectiveness Ratings and Use:

• 98% perfect use/ 80% typical use: Feminist Women's Health Center
• 80 - 98% typical use (for women who do abstain from intercourse during fertile times): Planned Parenthood

The What, the Why, the Where, the When, and the How-to: Fertility awareness methods work by a woman either only having genital intercourse during times when she knows or strongly suspects, through different ways of observation and record-keeping, that she is not likely to be fertile, or by being sure to use a backup method of birth control for any intercourse during those times.

We discourage our youngest users from trying to use fertility awareness as a sole method of birth control. In order for these methods to even have a chance of working a woman must have regular cycles which have been regular for some time, as well as the ability to chart and record fertility signals every day, and a partner who is deeply committed to doing his part to practice the method properly. It's normal for it to take up to five years for a woman's fertility and menstrual cycle to regulate, so even for Scarleteen users who began menstruating on the early side, it's not likely to be anything anyone can use as a sole method until they're at least 15 or 16, and for many women, a good deal later than that. Too, to use FAM effectively as a method of birth control, a woman usually needs to chart for at least six months before using it, a waiting period which young adults who want to become sexually active are not likely to find practical.

As well, many Fertility Awareness advocates teaching older adults will usually make clear that it is not a good method for any couple or woman who is not prepared for a pregnancy, even though, when practiced to the letter, it can be a highly reliable method. So, overall, we're more inclined to suggest using fertility awareness either just to know more about your body, as part of a combined method for users who do have regular periods and can handle the rigors of FAM, or for young couples who are trying to become pregnant, rather than trying to prevent pregnancy.

When we talk about Fertility Awareness here we are not usually talking about the rhythm method, or basing ideas on when a woman is most fertile only by averages for fertile times for all women. While that method is far better than nothing, because women's cycles vary, it is not as reliable as other methods of FAM: the standard days method is cited by Contraceptive Technology as 95% effective with perfect use, while other kinds of FAM are as much as 98% effective with perfect use. For those for whom the rhythm method -- sometimes called the standard days method -- is their only option, using Cycle Beads may help make that practice more reliable.

So, what ARE we talking about? Women using FAM effectively do so by using a number of different or combined methods each day, at the same time every day, to record and determine when it is most likely they will be fertile through sings her body gives about fertility. Those methods are any or all of the following: charting patterns of cervical mucus, taking daily basal body temperatures and/or direct cervical observation daily with the use of a mirror and speculum. Women's bodies do change daily in observable ways in response to the fertility cycle: when women observe and record those differences accurately over time, eventually -- so long as her cycles do not change or shift -- we can then draw conclusions from our observations to find out when we are or are most likely to be most and least fertile.

Women and their partners will then abstain from any genital intercourse during and around those times, or when they do not abstain, will use a very reliable method of contraception. Because the times to abstain are during the times when a woman is most fertile, it's vital that any intercourse during those times only happens with a highly reliable method. Since you can't have a natural fertility cycle while using a hormonal method, those are out, so we'd suggest something like combining condoms and a diaphragm, for example.

Couples may also choose to use FAM as a backup method, such as by using condoms as a method of birth control for all times a woman is NOT likely to be fertile, then abstaining completely during most fertile times. This is one way FAM can be an excellent combined method for young women whose cycles are regular, and who don't want to use hormonal methods.

Benefits of FAM can include that, save pregnancy if and when it occurs, there are no side effects, it allows a woman to have an incredible depth of knowledge about her reproductive cycle and body (which can be great even if you're already using another reliable, non-hormonal method simply because it can help you know when you just don't need to be freaked out about a risk -- cervical self-exams can also help you keep a lookout for vaginal infections), it can be a good way for couples to mutually commit to preventing pregnancy, and besides the cost of a basal thermometer, a speculum and mirror, paper and pen, it's free. For those whose religions or belief systems prohibit any hormonal or barrier methods, it is a method usually more effective than withdrawal, and one which also allows the woman more control. During infertile or less fertile times, for couples using it as a sole method, besides double-checking that it is a likely safe time, FAM does not interrupt sexual activity.

Not-so-greats include that it does require the cooperation of a partner, and often, the abstinence of a partner (and some women can feel tempted to take risks to avoid arguments at the time of sex) and oneself, a daily commitment to charting over time at the same time each day, and that there is a high risk of user error, especially for those without supervision.

For detailed information about how to do FAM right or get more information, see:

• Get With the Flow: All About FAM
• the Institute for Reproductive health @ Georgetown University
• The Fertility Awareness Center
• FAM information @ Advocates for Youth

It is also not advised to use FAM as a birth control method without the supervision and help of a teacher or coach, or, at the very least, a great book on the method. Two books we'd suggest for those interested are: Taking Charge of Your Fertility, by Toni Weschler, and The Garden of Fertility, by Katie Singer.

When Good Birth Control Does Bad Things: Because it is an entirely human-controlled method, with no added chemicals or devices, when FAM fails, it's 100% because of user error, either because a woman didn't keep up with charting, charted incorrectly, didn't make the correct conclusions based on her observations, or because she or her partner did not abstain or back up with a highly reliable method of birth control during her most fertile times.

Because many couples who use FAM will often have intercourse during infertile times unprotected, and because FAM requires the deep commitment of a partner to the method, as well as a readiness to become pregnant, it is generally best for women who are in long-term, monogamous and committed relationships where both partners are also known -- through testing and time -- to be STI-free.

Other methods which can be used as a backup method with FAM:

• Cervical Barriers (Diaphragms, Lea's Shield and Cervical Caps)

• Condoms
• Emergency Contraception (Plan B or the Morning-After-Pill)
• Spermicides
• the Sponge
• Withdrawal

Other methods you might like if you like FAM:

• Cervical Barriers (Diaphragms, Lea's Shield and Cervical Caps)

• Condoms
• Intrauterine Devices (IUD, IUC or IUS)
• Spermicides
• the Sponge
• the Vaginal Ring (Nuvaring)
• Withdrawal

Why would FAM be a good option for me? If any of the following are true:

• You want a method which has absolutely no side effects
• You are a compulsive note-taker
• You want to know as much as you can about your own body, and can commit to observing yourself at the same time every day
• You are looking for a method which is allowed by religions or belief systems who prohibit hormonal or barrier methods
• You want something which is very inexpensive
• You want something which is either quickly reversible, or which when you know you want to become pregnant, will help you in creating a pregnancy
• You are in a long-term, committed, monogamous relationship where both partners are STI-free
• You want a method which both partners can be an integral part of
• You are currently breastfeeding

For a brief overview of all methods, have a look at Margaret Sanger's Disneyland: Choosing Contraceptives. Want to start over with Birth Control Bingo? Click here.

Don't forget: Statistically, sexually active young adults are as, if not more, likely to acquire a sexually transmitted infection (STI) as you are to become pregnant. Although 15-24-year-olds represent only one-quarter of the sexually active population, they account for nearly half of all new STIs each year, and of the 18.9 million new cases of STIs each year, 9.1 million (48%) occur among 15-24-year-olds (AGI). Often people have some funny ideas about who is most likely to get an STI, but the fact of the matter is that younger people -- of any sexual orientation, any economic class, any kind of relationship -- have been the highest risk group for some time now.

Condoms are the only method of birth control which also provide protection against STIs. It's pretty typical for younger people to ditch condoms if they have another method of birth control, so just remember that STIs are still a risk if you're using another method. You can read all about safer sex here -- Safe, Sound & Sexy: A Safer Sex How-To -- but the rule of thumb most medical experts and prevention organizations suggest, which we also encourage at Scarleteen is six months of safer sex, six months of sexual monogamy, and then TWO full STI screenings for each partner -- once at the start of that six months, once at the end -- before ditching latex barriers.