National Catholic Register

Culture of Life

Study Confirms Creighton Method’s Reliability in NFP

Medical journal cites 99.5% effectiveness rate in preventing pregnancy

BY Ellen Rossini

August 09-15, 1998 Issue | Posted 8/9/98 at 2:00 PM

 

DALLAS—The Creighton method of natural family planning (NFP) is roughly as effective as the birth control pill when used to avoid pregnancy, according to a 14-year, five-state study published this summer in a U.S. medical journal.

The study, which appeared in the June issue of the Journal of Reproductive Medicine, distributed to obstetrician-gynecologists, showed the method to have a 99.5% rate for method effectiveness, that is, when it is taught and used precisely, and a 96.8% use effectiveness rate, a “real-life” rate that includes teaching or use errors.

Current research shows oral contraceptives to have a 97.0% user effectiveness rate, according to the report. The study also quotes that among the reversible methods of preventing pregnancy, as opposed to surgical sterilization, the injectable hormonal contraception has the highest use effectiveness rating, of 99.8%, and the intrauterine device has a 98.0% use effectiveness rating. Unlike NFP, such methods are contrary to Church teaching as artificial contraception and because they often function as abortifacients, preventing a fertilized ovum from implanting in the womb.

Another finding in the report was that while the method effectiveness has remained stable through the 14 years of study at between 98.7 and 99.8 out of 100 couple years, the use effectiveness appears to have improved over time. The earliest use effectiveness was 94.6%, which increased to 97.9% in the most recent study.

The report, the latest published analysis of ongoing research by the Pope Paul VI Institute based in Omaha, Neb., evaluated 1,876 couples at five reproductive health centers that teach the Creighton method and included more than 17,000 couple-months of use. The large scope of the study and its statistical protocol, including life-table analysis, qualified it to appear in a peer-review journal, according to co-author Dr. Thomas Hilgers, founder and director of the institute, a national Catholic center of reproductive study and services.

“There has been quite a bit of unevenness in the literature. When it comes to effectiveness measures in general terms, there aren't very many people who understand how [statistical studies are done],” Hilgers said. “It's really a very strong study. [The Creighton method] is as good as birth control pills and better than anything else on the market.”

The Creighton method is a standardized version of the Billings ovulation method that relies on a woman's observation and charting of changes in her cervical mucus to determine her fertility.

The article is the most recent of a number of effectiveness studies of NFP to appear in professional journals since the early '90s, according to Theresa Notare, NFP specialist for the National Conference of Catholic Bishops.

“Anytime you get yet another good study in a serious journal, that enhances the prestige of NFP as a viable family planning method,” she said.

However, the key to increasing the use of NFP beyond 2% to 3% of couples of childbearing age using natural methods to avoid pregnancy is not so much medical recognition as good local programs, she said.

“What would make a difference in your Catholic church is really good teachers — that old-fashioned missionary work,” Notare said. “That will make a significant contribution to putting aside the prejudice and putting aside the ignorance [about NFP].”

Dr. Joseph Stanford, assistant professor at the University of Utah medical school, co-wrote the study with Hilgers as part of his association with the Creighton method since 1991.

“I've gradually seen a little more openness [in the medical field toward NFP]. I think that this [study] will help,” he said. “I'm expecting that there will be some discussion and controversy about this study. I'm looking forward to what comes out of that.”

One possible point of contention is the demographics of the study, which skewed to better-educated, middle- to upper-middle-class couples and Catholics, said Stanford.

“I think that's more a function of culture than the method,” and should not detract from its validity, he said, likening it to breast feeding, which skews to a similar group who are more interested and have more access to instruction.

Studies of similar NFP methods have been done in Third World countries with high-effectiveness results, Stanford added.

Another point of controversy, particularly within the NFP movement, is the Creighton model's calculation of “informed choice” pregnancies — those pregnancies that result when a couple spontaneously choose to have intercourse during a time they correctly determined as fertile.

“That particular category is absent from the Creighton model,” therefore the user effectiveness rate appears higher than for other NFP methods, according to Sister Hanna Klaus, a medical doctor and executive director of the Natural Family Planning Center of Washington, D.C.

According to the article, Creighton couples are instructed that the method may be used to avoid or achieve pregnancy, and that when they choose intercourse on a day of fertility they have de facto switched from being “avoiders” to being “achievers.” In this way they are separated from the statistics for pregnancy avoidance.

A separate paper will be published soon on the successes of the “achievers,” Hilgers said.

Despite their difference in approach, Sister Klaus — a promoter of the Billings method who is currently working in teen chastity — said Hilgers has worked “hard and long” on his model and has heightened the professionalism of NFP among family practice physicians.

“That's something to be very much welcomed,” she said.

Dr. Konald Prem, a pioneer of the modern method of NFP who helped develop the Sympto-Thermal Method promoted by the Cincinnati-based Couple to Couple League, cheered the inclusion of the study in the journal, but also found a few gaps.

For example, the report did not mention how many actual pregnancies occurred, he said. Also, he agreed with Sister Klaus that some note has to be made of those couples who take chances with the method because they would not be concerned about a pregnancy if it occurred.

“A lot of these people are ‘spacers.’

If they get pregnant, it's all right anyway,” he said. “They should be talked about.”

Finally, he said, the Creighton study includes some older women of declining fertility and breast feeding women, who can be at a low risk for pregnancy.

Dr. J. Patrick McCarty, a Dallas area ob-gyn with 35 years of practice, does not prescribe artificial contraception for his patients but refers women for education in NFP. He said he found the report interesting and well-done, but is not optimistic about its changing the minds of most in his field.

“I unfortunately don't think it's going to sway any of them,” he said. “We really as a specialty of obstetrician-gynecologists believe women can't know, they can't understand their bodies. That's really pretty demeaning and paternalistic.”

The NCCB's Notare believes it will take leading contraceptive researchers to do a serious study of NFP before it can break into the mainstream, but that acceptance is not necessarily the goal for a family planning approach that includes openness to life as part of a couple's spirituality.

“I don't know how good it would be for NFP to be co-opted by the family planning industry,” she said. “Ours is a holistic vision that these people just don't have.”

Ellen Rossini writes from Dallas, Texas.