Current Medical ResearchWinter/Spring 2014

The data for this study were prospectively collected among women seeking NFP services in a university-based online NFP education and service program managed by advanced practice professional nurses. Before receiving access to the Web site the participants signed a consent form for participation and the study received human subject approval through the Marquette University Office of Research compliance. The online Web site is encrypted through an external cloud server system and is accessed only through protected passwords. The personal information of the participants and their fertility charts can be accessed only by the professional nurse NFP teachers or a vetted graduate research assistant at Marquette University. The Marquette University College of Nursing NFP web site (http://nfp.marquette.edu) has free information on fertility, a downloadable user manual and charting system, protocols for special circumstances (e.g., use of NFP postpartum), and instructions for achieving and avoiding pregnancy. A unique aspect of the information section of the web site is one page simple Quick Start Instructions that can be read in five minutes and allows the user to begin charting and using a NFP method right away. Women who register on the Web site are able to access an online electronic charting system, discussion forums, and have consultation from professional nurse NFP teachers, an obstetrician-gynecologist with expertise in the use of NFP, and a bioethicist. The online charting system also notifies the user of possible health problems, including unusual bleeding, infertility, and cycle dynamics that are out of the norm. The Marquette online NFP system is offered in both the English and Spanish languages. The online charting system has designated sections for recording the results of the EHFM or self-observed cervical–vaginal mucus. The charting system has pop-up windows that illustrate the three fertility levels provided by the fertility monitor or the cervical–vaginal mucus observations. The estimated day of ovulation (EDO) was either determined by mucus peak or the monitor peak, i.e., the day of the menstrual cycle with the last peak reading for either monitor or mucus. The length of the luteal phase was calculated from the day after either the last monitor or mucus peak rating and ended the day before the next menses. Information from the online menstrual cycle charts were accessed from the Web site by graduate student research assistants and entered into a statistical program data file (SPSS version 21). Descriptive statistics were used to determine the percentage of the day of peak mucus days (i.e., the mucus EDO) that fell plus or minus two days of the monitor EDO. Pearson's correlations were calculated between the EDO of mucus and monitor and between the first high ratings of mucus and monitor. Paired t-tests were used to determine differences between the monitor and mucus determined EDO, the luteal phase length, the first recorded high day, the total number of high days per menstrual cycle, and the total estimated fertile phase, i.e., the total high and peak rated days of fertility. Since there was a series of t-tests, to control for error rates, the Bonferroni correction average of 0.05/5 = 0.01 was the level of accepted significance.

Correlation of High and Peak Mucus Days with Peak LH There were thirty-eight participants from the pilot study that charted both cervical mucus observations and fertility levels from the EHFM. They produced 329 usable charts of menstrual cycle data. Of these cycles, 255 had both a recorded peak in mucus and peak monitor recording, 50 (15.3%) of the 329 menstrual cycles had no peak mucus recorded and 47 (14.5%) of the menstrual cycles had no monitor peak recorded. The percentage of peak mucus days that were within plus or minus 2 days of the monitor EDO (i.e., the day after the LH surge) was 245 or 96 percent of the cycles. The Pearson correlation statistic between the EDO by CMM and EHFM estimates was r = 0.96 P < 0.001. The correlation between the first high reading between CMM and EHFM was r = 0.47, P = <0.001, and the correlation of the total length of fertile days (highs plus peak readings) was r = 0.31, P = <0.001. Mucus (CMM) and Monitor (EHFM) Estimated Fertile Days of the Menstrual Cycle As seen in table 1, there were significant statistical differences in the estimation of the day of ovulation (i.e., the EDO) the length of the luteal phase, and the determination of the first High day by CMM with that of the EHFM as determined by serial paired t-tests. The total fertile days were statistically similar between CMM and EHFM monitoring. Table 1 . | Mucus monitoring | Hormonal monitor | ||| |---|---|---|---|---| | Mean (SD) | Mean (SD) | t-test | P< | | | Day of EDO* | 16.36 (3.99) | 16.90 (3.69) | 7.67 | 0.001 | | Luteal phase** | 12.26 (2.28) | 11.70 (1.94) | 7.45 | 0.001 | | First high day*** | 11.47 (3.12) | 13.06 (3.82) | 7.57 | 0.001 | | Total high days | 4.36 (2.55) | 5.12 (4.34) | 2.81 | 0.005 | | Total days of fertility | 8.80 (3.15) | 8.40 (3.21) | 1.82 | 0.070 | *EDO, the number of days of the menstrual cycle from the first day of menses up to and including the estimated day of ovulation, i.e., the peak mucus day and day of the second peak recording of the hormonal monitor. This is also the follicular phase length of the menstrual cycle. **Luteal phase = the number of days of the menstrual cycle counted from day after EDO as estimated by the peak mucus or the monitor peak and up to the day before the next menses, i.e., to the end of the menstrual cycle. ***The day of the menstrual cycle when the first high rated mucus was recorded or the first high reading of the monitor was recorded.

This small study demonstrated that a simple method to teach and rate cervical mucus observations for determining the fertile phase for use in NFP has been further validated by comparing with an EHFM that measures E3G and LH. Specifically, the peak in cervical mucus as determined by this simplified method of NFP correlated very closely with the LH surge and peak reading of an EHFM. The 96 percent correlation of plus or minus 2 days of the LH surge by the EHFM with the peak in cervical mucus is close to the results that was found by the Parucznick et al.’s (2014) study (92%) with a smaller number of menstrual cycles. So too, the strong high positive statistical correlation between the peak in cervical mucus and the urinary LH surge of 98 percent is similar to the findings of other studies (Fehring 2002). Although this study showed statistical differences in estimated parameters of the menstrual cycle as determined by CMM and EHFM, the differences might not have clinical relevance. The fact that the average mucus high day came before the EHFM high reading would not be a problem with NFP, in fact, the early mucus high would make the method a tad more conservative and maybe more secure. A concern would be that there might be excessive days of fertility and required abstinence. However, the length of the total days of fertility, i.e., the total of high and peak days is very similar between the two methods of estimating fertility. An earlier study by this author compared the estimated fertile phase by CMM with a more detailed mucus grading system (i.e., a 1–8 scale). This method of mucus ratings resulted in considerably more days of fertility compared with the EHFM (Fehring, Schneider, and Raviele 2004). The current simplified system of rating mucus as low, high, and peak seems to have eliminated extended estimated fertile phases when mucus is of a continuous or low grade nature. The strength of this study is that it involved a fairly large data set of menstrual cycles that compared the CMM estimated days of fertility with an EHFM by the same woman with each menstrual cycle. Parucznik et al.’s (2014) study only generated thirty-nine cycles. A limitation is that the EHFM was not blinded to the users and thus could have influenced the rating of the cervical mucus. Although this study provided evidence to validate the accuracy of the CMM estimate of the EDO and fertile phase of the menstrual cycle, the real clinical concern would be whether the simplified mucus method is effective in helping couples avoid (or achieve) pregnancy and provides confidence and satisfaction with the consumer. An earlier pilot study showed a correct use of 98 percent and typical use of 90 percent in avoiding pregnancy among non-postpartum breastfeeding participants using either the EHFM, CMM, or both to estimate the fertile phase of the menstrual cycle. This study was too small to determine if there were differences among the CMM only participants and the EHFM participants or the participants who used both EHFM and CMM to estimate the fertile phase. An extended use study with a much large population of women (i.e., greater than 1,000 participants) will allow us to analyze subgroups and determine the effectiveness of the simplified CMM. Biography Richard J. Fehring is professor emeritus, Marquette University College of Nursing, Milwaukee, Wisconsin, USA. His email address is [email protected].

- Arévalo M.1997. Expanding the availability and improving delivery of natural family planning services and fertility awareness education: providers' perspectives. Advances in Contraception 13: 275–81. [DOI] [PubMed] [Google Scholar] - Arévalo M., Jennings V., and Sinai I.. 2002. Efficacy of a new method of family planning: the Standard Days Method. Contraception 65(5): 333–8. [DOI] [PubMed] [Google Scholar] - Arévalo M., Jennings V., Nikula M., and Sinai I.. 2004. Efficacy of the new twoday method of family planning. Fertility and Sterility 82: 885–92. [DOI] [PubMed] [Google Scholar] - Fehring R.2002. Accuracy of the peak day of cervical mucus as a biological marker of fertility. Contraception 66: 231–5. [DOI] [PubMed] [Google Scholar] - Fehring R.2005. New low and high tech calendar methods of family planning. Journal of Nurse Midwifery and Women's Health 50: 31–7. [DOI] [PubMed] [Google Scholar] - Fehring R., Raviele K., and Schneider M.. 2004. A comparison of the fertile phase as determined by the Clearplan Easy Fertility Monitor and self-assessment of cervical mucus. Contraception 69: 9–14. [DOI] [PubMed] [Google Scholar] - Fehring R., Schneider M., and Raviele K.. 2011. Pilot Evaluation of an Internet-based Natural Family Planning Education and Service Program. Journal of Obstetric Gynecologic and Neonatal Nursing 40: 281–91. [DOI] [PubMed] [Google Scholar] - Fehring R., Schneider M., Raviele K., Rodriguez D., and Pruszynski J.. 2013. Randomized comparison of two Internet-supported fertility awareness based methods of family planning. Contraception 88: 24–30. [DOI] [PubMed] [Google Scholar] - May K.2001. Home monitoring with the ClearPlan Easy Fertility Monitor for fertility awareness. Journal of International Medical Research 29(Suppl 1): 14A–20A. [DOI] [PubMed] [Google Scholar] - Porucsnik C., Cox K.J., Schliep K.C., and Stanford J.B.. 2014. Pilot test and validation of the peak day method of prospective determination of ovulation against a handheld urine hormone monitor. BMC Women's Health 41(4): 1–9. [DOI] [PMC free article] [PubMed] [Google Scholar] - Trussell J.2011. Contraceptive failure in the United States. Contraception 83: 397–404. [DOI] [PMC free article] [PubMed] [Google Scholar]