Natural Family Planning International

Your Right to Know: The Cervix Sign

As indicated in the August 11 post of Dr. Edward F. Keefe’s COVERLINE article on the internal observations of cervical mucus, his patients taught him about changes in the cervix itself, changes that had not been previously reported in the medical literature. He first reported on this in 1962 in the Bulletin of the Sloane Hospital for Women. Fifteen years later he reported it in the International Review of Natural Family Planning, Vol.1, Number 1, Spring 1977. It is interesting both in its detail and in the responses he gives to questions about its effectiveness when used in systematic NFP.

As Dr. Keefe indicates in this article, squeamishness hinders some women from ever making the exam, and he addresses that issue. He never advocates a cervix-only system for purposes of avoiding pregnancy. In NFPI we teach the observation of the cervix as a supplement to the mucus and temperature signs. Experienced women have told us that the cervix sign is sometimes the best sign for them about their fertility or infertility, especially in extended breastfeeding amenorrhea or during premenopause.

If you would like to read his 1977 report, see www.naturalfamilyplanningandmore.com/Cephalad_Shift_of_the_Cervix_Uteri.pdf.

John F. Kippley

Your Right to Know: The Temperature Sign

The temperature sign is an extremely valuable component of the science and art of natural family planning.

•An elevated temperature pattern provides a positive sign of being past ovulation.
•It provides a highly accurate way to determine both the beginning of the fertile time and the end of the fertile time.
•Twenty-one days of elevated temperatures provide a 99% degree of certainty that you have achieved pregnancy.
•It provides the single best predictor of the date of childbirth, and it takes only a few minutes to take one’s waking temperature.
•It can be used by itself, and it can also be used in a cross-checking way with the cervical mucus.

You have a God-given right to know all these God-given realities about the temperature sign.

Here’s a brief summary of how this information developed, and in what follows, Phase 1 = pre-ovulation infertility; Phase 2 = the fertile time; Phase 3 = post-ovulation infertility.

In 1877 Mary Putnam Jacobi found that a menstruating woman’s temperature rises about mid-cycle and remains elevated until the start of menstruation. She was a feminist of sorts, seeking to prove that menstruation was not a sickness that prevented women from working outside their homes.

A person of great interest to NFP history is Rev. Wilhelm Hillebrand, a German Catholic priest who had a scientific mind and simply wanted to help his parishioners. In the very early 1930s he was aware of the “rhythm” work of Dr. Kyusaku Ogino and Dr. Hermann Knaus and began advising couples according to the Knaus calendar-rhythm formula. Soon he had reports of three unplanned pregnancies. Then he remembered the temperature-based research of Dr. T. H. van de Velde reported in 1926.

In 1935 Fr. Hillebrand collected 76 temperature graphs from 21 women, and from this he invented the Calendar-Temperature method as it would be later called. In this system, a previous-cycle calculation such as “Shortest cycle minus 19” was used to determine the end of Phase 1, and Hillebrand’s genius was to insist that elevated temperatures were required to establish the beginning of post-ovulation infertility. He thus eliminated the weakest side of calendar rhythm. (The 19 Day Rule has since been changed to the 21 Day Rule and the 20 Day Rule.)

Over the years, various doctors contributed to our understanding of how to interpret temperature graphs for the start of Phase 3, and they also contributed to increasing the effectiveness of previous-cycle rules for the end of Phase 1. But there was nothing by way of published effectiveness data.

In 1967 Dr. G. K. Doering of Germany made a significant contribution to the science of natural family planning with his temperature-only study published shortly before Humanae Vitae. See the translation of his report at http://www.nfpandmore.org/Doering-1967-100315.pdf . Of great significance is that his “end-of-Phase 1” rule is based on the temperature pattern. This was unique because previous researchers had used an end-of-Phase-1 rule based on the length of the entire cycle such as “Shortest cycle minus 19.” Doering based his calculation on the first day of thermal shift in previous cycles, thus eliminating variations based on the length of the luteal phase (the days between ovulation and the start of the next menstruation).

In his study, Doering gives us statistics for two different groups— (1) those who engaged in the marriage act both in Phase 1 and in Phase 3, and (2) those who limited their marriage acts to Phase 3. In the first group, he found a 96.9 percent effectiveness rate that included all the marriage acts in what was clearly Phase 2. In the Phase 3-only group, the effectiveness rate was 99.2 percent. This was a temperature-only system with no cross-check from the disappearance of cervical mucus.

Dr. Konald Prem decided in the early 1970s that we could modify the Doering Phase 3 rule into a cross-checking sympto-thermal rule by requiring that that the three days of high-level temperatures must be cross-checked by a minimum of two days of mucus drying up to assure that the temperature rise is due to ovulation and not a cold or sickness. When this rule can be applied, it provides the earliest start of Phase 3 of any of the other STM or the mucus-only rules. In NFP International, we call this Rule K.

Konald Prem has also given us an accurate temperature-based rule for estimating the date of childbirth (EDC). The rule that doctors used almost universally previous to this time was the Naegele rule from the mid-19th century: start with the first day of the last menstrual period, add 1 year, subtract 3 months, and add 7 days—approximately 40 weeks. It works quite well when a woman ovulates about cycle day 14, but it is increasingly inaccurate when ovulation occurs a number of days after day 14, and it is worthless when a breastfeeding mother conceives before she has her first period.

The Prem rule uses the rise in post-ovulation temperatures. Take the first day of elevated post-ovulation temperatures, subtract 7 days and add 9 months. In a mid-Seventies article in a medical journal,he wrote that this is the most accurate way to predict the EDC, more accurate than much more elaborate and expensive procedures such as “estimation of uterine size by palpation or measurement, the dates of quickening and engagement of the fetal head and auscultation of the fetal heart tones with the head stethoscope…” or “biochemical and biophysical methods such as estriol, ultrasound and phospholipids…” (Konald A. Prem, “Assessment of Gestational Age,” Minnesota Medicine, September 1976, 623). For examples of how this knowledge has helped to avoid a premature induction of labor and to require an insurance company to cover the expenses of a premature baby, see page 70 of our manual, Natural Family Planning: The Complete Approach.

Breastfeeding mothers who conceived many months postpartum and before their first menstruation have expressed great gratitude for the Prem temperature-based rule.

Other benefits of recording temperatures are found when women experience breakthrough bleeding and irregular shedding. These are also described in our NFP manual. Among many married couples, a significant advantage of using the temperature sign is that it gets the husband involved, and this can be very helpful.

The weakness of the temperature sign is that when ovulation is significantly delayed, as happens during breastfeeding infertility and during premenopause, it does not signal the start of Phase 2. However, it does confirm continued non-pregnancy as long as the temperatures remain low. A second weakness, if it can be called that, is that it is so easy to take and record daily temperatures that some women ignore their mucus signs. I once heard Dr. John Billings cite this as a reason why he switched to a mucus-only system.

In NFP International we strongly recommend using both the mucus and the temperature in a cross-checking way.

We know that the elevated temperature reflects elevated levels of progesterone that is secreted by an ovarian follicle, the corpus luteum, after ovulation. I do not know why this hormone causes a woman’s waking temperature to rise, but it is a God-given reality.

And you have a God-given right to know these realities.

John F. Kippley

Your Right to Know: The Internal Observations

As noted in the previous posting dealing with cervical mucus, Dr. Edward F. Keefe was the first doctor of record in the United States to promote and teach the observation of cervical mucus, starting in 1948 or 1949 with a reference in his Ovulindex thermometer booklet and more specifically with an illustration in the 1953 edition of that booklet. He wanted the mucus and temperature signs used in a cross-checking way, and he was thus opposed to the Billings emphasis on using it by itself. In 1975 he wrote the following review of the Billings’ book. This appeared in COVERLINE, the newsletter of the Natural Family Planning Association of Connecticut, Spring, 1975. Since he is the pioneer in this area, I thought it would be worthwhile to have his opinions available on the internet.

“Reflections on Mucus Alone as a Fertility Sign” by Edward F. Keefe, M.D.   A strong tone of advocacy marks Dr. Billings’ book, Natural Family Planning, the Ovulation Method, 2nd American edition. While its shortcomings are now well recognized in spite of the enthusiasm of its proponents, I welcome a chance to “place in the record” a review of this book.

Preparing the review brought to mind my early efforts to improve systematic abstinence as a means of family limitation. I recalled my excitement over a paper on the rheology of human cervical mucus (1. Clift, A.P., Proc. Roy. Soc. Med. 39:1945). Rheology is the study of flow. Women apply it every day when they judge such things as syrups, jellies, batters, ripeness of fruit, etc., in the kitchen. The paper made me wonder if a woman could not observe for herself the changes in the physical properties of her cervical mucus as well as its volume, changes which already could signify the fertile time in farm animals. I reported on preliminary studies of these aids in 1950 to a meeting of the medical staff of St. Vincent’s Hospital of New York. They listened politely but many questioned if there was a fertile time in women at all, not whether it could be recognized by temperatures or mucus.

The Ovulindex thermometer had just been developed by me. (I should disclose I still own the company that manufactures it.) In 1948 I wrote (anonymously) its first handbook, which said no more about mucus, I find now, than that its presence was to be recorded, along with the temperatures. But, by 1953, I was so confident that changes in the mucus were a valuable guide that I fully described them in the second edition. I illustrated the location of the cervix and how to test threading of the mucus between thumb and forefinger – a rheologic test.

In my office practice, at first I, too, taught the use of the mucus on the vulva, as does Dr. Billings. But it was insufficient, inconstant, and lagged beyond the true state of the ovaries according to my patients. Most of them had been “Rhythm-failures” many times over and they demanded perfect results. The best mucus sample was needed and the place to find it was in the cervical canal, unaffected by passage through the vagina. I encouraged them to remove the mucus directly from the cervix. After trying aspiration through a tube, we settled on removing the mucus with the fingers. In making such collections, my patients discovered there were changes in the cervix itself. They found at the approach of ovulation, as the mucus became abundant, thin and clear, the cervix itself softened and the canal opened. A search of the medical literature disclosed descriptions of this dilation of the canal, but to apply these changes to periodic abstinence was something new. I studied them for more than ten years. Many women were enthusiastic about the signs and asked why they did not receive more publicity. Meanwhile, my paper on this seemed to create little interest among doctors (2. Keefe, E.F., “Self-observation of the Cervix to Distinguish Days of Possible Fertility” Bull. Sloane Hosp for Women, 8:129, 1962). The spotlight was on Dr. Rock’s “100% effective pill.”

Somewhat later, my patients reported to me that the cervix is elevated as well into the pelvis before ovulation and descends after it. These were astonishing changes not mentioned in the literature. I felt certain enough of these signs to describe them in 1964 in the third edition of the Ovulindex thermometer handbook and in COVERLINE: Vol. 2, No. 4, 1970.

Meanwhile, Dr. Billings lectured to our obstetrical staff at St. Vincent’s and when he returned to Australia, his home, he kindly sent me The Ovulation Method, first edition (1964) which explained calculation of the cycle-pattern, temperature charting and the changes in mucus. In 1965, I learned from Dr. Lanctot that mucus was a “symptom” in the Sympto-Thermic Method. I was happy that others were working along the same lines as myself.

Just recently, Dr. Josef Roetzer of Voecklabruck, Austria, in explaining his sympto-thermal system at a “Round Table on Ovulation Prediction” in Rome, on April 4-6, 1974, described the changes in the cervix mentioned above, including its elevation at the fertile time. His patients, like mine, had discovered for themselves these signs. I still believe (2) “It could become common knowledge that, if a woman finds her cervix flaccid, gaping and streaming with mucus, there is a great chance of conception and, in the absence of these signs, there is less or no chance.” Dr. Billings’ book will help disseminate part of this knowledge and for that I welcome it. But I would rather that mucus signs supplement the charting of temperature, not replace them as the book demands. Moreover, just because mucus on the vulva is not a dependable sign, its shortcomings must not cause us to undervalue the changes in the cervical mucus and the cervix itself. I will go into this in a forthcoming book review.

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We do not have his book review. To see how all the signs are used in a cross-checking way, see our manual, Natural Family Planning: The Complete Approach at http://www.nfpandmore.org.

John F. Kippley