Jan. 1, 2001 -- Nathan and Kathy Sendan begin each day with a pen, paper, and digital thermometer. The El Sobrante, Calif., couple dutifully record Kathy's basal body temperature before they even think of drinking their morning coffee. Then they combine the temperature readings with other physiological data to track Kathy's fertility cycle and, in effect, to time sex.
Such is the routine for those who practice natural family planning, a method that shuns hormones, condoms, and other artificial forms of birth control. It is the only form of contraception given the stamp of approval by the Catholic Church, but many proponents see a growing interest among non-Catholics as well.
Joseph Stanford, MD, assistant professor of family and preventive medicine at the University of Utah and former president of American Academy of Natural Family Planning, estimates that as many as 40% of those now practicing this technique are non-Catholics. Natural family planning "offers an alternative where you don't have to mess up your physiology -- you're more in tune with your body, and there are no side effects," Stanford says.
"It's not just a Catholic thing anymore," says Patrick Homan, the western region field director for the Couple to Couple League, an Ohio-based institute whose 1,351 teachers offer instruction on natural family planning. "Our numbers have been going up for the last five to six years."
Indeed, the Sendans are not Catholic, but they chose natural family planning because of dissatisfaction with the pill. "I liked the idea of not putting chemicals in my body," says Kathy Sendan.
She recalls being "grumpy all the time" during the three years she was taking oral contraceptives. She also had a more specific health concern: "I have epilepsy, and the [antiseizure medication could] have made the birth control pill less effective," she says.
Numbers Remain Small
To be sure, the number of people choosing natural family planning still remains small. According to a 1995 survey conducted by the National Center for Health Statistics, only 1.5% of women aged 15-44 reported using periodic abstinence as a means of contraception. That trails the 17.3% of women choosing the pill, the most popular form of reversible contraception. Female sterilization was the most popular method at 17.8%, followed by the condom at 13.1%. Advocates of natural family planning say their efforts are hampered by the stigma of the "old" calendar rhythm method, which relied on the expectation that ovulation occurs on Day 14 of a 28-day cycle, and resulted in numerous "surprise" pregnancies.
In fact, menstrual cycles can vary from one woman to the next, and for many women, from one month to the next. Stress or illness, for instance, can disrupt even the most regular cycles. Such inherent variability was recently demonstrated in a study of 221 healthy women, published in the British Medical Journal in November 2000. Using daily urine tests to check for hormonal evidence of ovulation, researchers from the National Institute of Environmental Health Sciences found that even though clinical guidelines assume the average woman is fertile between days 10 and 17 of her menstrual cycle, only 30% of the women studied had their window of fertility fall entirely within that time period. Even women with reportedly regular cycles had a 10% chance of being fertile "on any given day of their cycle between days six and 21," the researchers wrote.
"What was surprising to us is the fact that not only were fertile days coming early in the cycle, but late when a woman thinks she's on the end of her cycle," says Allen J. Wilcox, MD, PhD, chief of epidemiology at the NIEHS and lead author of the study. "We're just putting numbers on something people had a sense of before."
The researchers also point out that most of the women in the study were between the ages of 25 and 35. Teenagers and women nearing menopause tend to have even more unpredictable cycles.
It's Not Guesswork
Homan calls the calendar rhythm method "a guessing game, pure and simple," but emphasizes that there is more to natural family planning than just counting days. The more modern variations rely upon physiological signs such as changes in cervical discharge, body temperature, cervix position, or if it's the "sympto-thermal" method, a combination of all three, to signal whether a woman is fertile. "Modern natural family planning doesn't try to predict anything," he says. "It's, 'What you see is what you are.'"
Using these indicators, he says, a woman should be able to tell when she is in the preovulation, fertile, or postfertile phase of her cycle. Couples attempting to avoid pregnancy either can abstain from sex during the fertile phase or use other forms of protection.
Done correctly, it can be highly effective, says Stanford from the University of Utah. Stanford co-authored a study of 1,876 couples using a method of natural family planning that relied upon changes in cervical mucus to chart fertility. The study, published in the June 1998 issue of the Journal of Reproductive Medicine, found the technique had an impressive 96% effectiveness rate in preventing pregnancy, comparing favorably to condoms and diaphragms, though still less reliable than the pill or sterilization.
So why aren't more people embracing a birth control method that is free, safe, and effective?
For one thing, natural family planning is not widely promoted among healthcare professionals, says Ron Gronsky, PhD, professor of materials sciences at the University of California at Berkeley. "It's a lot easier for a practicing physician to prescribe [a pill] than to discuss and counsel," says Gronsky, who with his wife, Andrea, teaches natural family planning to other couples.
Andrea Gronsky recalls how information on natural family planning was even scarcer two decades ago. "When we first got married, we didn't know how to do it" because guidance was hard to find, she says. She says she used breastfeeding, which can stave off ovulation and menstruation, as a form of contraception after the birth of their first child. Soon after, the Gronskys, both of whom are Catholic, switched to the sympto-thermal method of family planning, which they have used for 26 years.
Not for Everyone
But the Gronskys also acknowledge that natural family planning isn't for everyone. The method, they say, is best suited for stable, monogamous couples, and they limit those they train to engaged or married couples.
Natural family planning also "involves more effort," says Lindy Pasos, development director for Planned Parenthood Mar Monte in Nevada. "Our position is that we're thrilled that people are using family planning and thinking about when they want to have children." But she says checking physiological signs every day takes discipline and more commitment than many people are willing to make.
Some also may find it difficult to cope with the seven- to 10-day abstinence period when the woman is fertile. "Sexual spontaneity in this country is a big deal," says Pasos. "Many people don't want to think about birth control all the time."
And because this method offers no protection against sexually transmitted diseases (unlike, for example, condoms), it is not an acceptable choice for those with multiple sexual partners.
Still, many proponents of natural family planning find it easy to follow the routine once they get used to it. "The measurements you take every day are really easy," says Beth, a doctoral student at the University of California at Berkeley. She and her husband, Peter, who asked that their last name be withheld, started using natural family planning a year ago. "The temperature part is a piece of cake."
Best of all, she says, she has gained more control of her health and has become her body's best expert. "I'm actually proud of how much I know about my body now," says Beth. "I notice changes I'm going through every month. I know my fertility cycle. I feel more in touch with my body."