A growing number of teenagers are trying to use the rhythm method for birth control, according to a survey by the National Center for Health Statistics (NCHS). The rhythm method, also called the calendar method, calendar rhythm method or periodic abstinence, is a type of natural family planning. To use the rhythm method, you track your menstrual history and use a calendar calculation to predict when you'll ovulate. Based on this prediction, you can determine which days to avoid unprotected sex.
Successful use of the rhythm method takes more than just identifying the woman's most fertile days and avoiding intercourse on those days. You also need the discipline to abstain from intercourse for several days before ovulation, as well as during ovulation and for a few more days afterwards. If you and your partner aren't comfortable talking about sex, or if you generally avoid sexual activities other than intercourse, the rhythm method is not right for you. Out of about 100 typical couples who use the rhythm method for a year, 22 will get pregnant. In other words, the rhythm method is about 78 percent effective.
No statistics are available on teen pregnancy due to rhythm method failure. But the survey cited at the top of this blog, based on interviews of thousands of teenagers about their sexual behavior, contraceptive use and childbearing, 17 percent of sexually experienced girls said they had used the rhythm method for birth control. That's a striking increase since 2002, the last time this survey was conducted. In 2002, only 11 percent — still too many — reported using the rhythm method.
The rhythm method is a poor birth control choice for teens as some may lack the emotional maturity to track their fertility and abstain from sex for several days a month. But there's another obstacle that may trip up even the most stable and responsible teen couple favoring the rhythm method: Teenage girls may take several months to establish regular menstrual cycles, so they might find it particularly hard to calculate their fertile and safer days. Stress, illness and many other factors can also alter your cycle. This unpredictability may be one reason why teen pregnancy rates rose from 2005 to 2007, after a steady decline starting in 1992. In 2008, teen pregnancies declined again, but only by 2 percent.
Remember, too, that the rhythm method protects neither partner against sexually transmitted diseases. Unless you've both been tested and found to have no STDs — and you're both absolutely committed to your monogamous relationship — you should use a condom every time you have intercourse, preferably along with a hormonal contraceptive, such as birth control pills. Responsible, caring sex partners want reliable birth control as well as protection from STDs. For most young people, the rhythm method fails on both counts.
blog index References Abma JC, et al. Teenagers in the United States: Sexual Activity, Contraceptive Use, and Childbearing, National Survey of Family Growth 2006-2008. National Center for Health Statistics. Vital Health Stat 23 (30). 2010. http://www.cdc.gov/nchs/data/series/sr_23/sr23_030.pdf. Accessed Aug. 4, 2010.
