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Modern Rhythm

Finding 'Safe' Sex Days

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.

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