Fertility and the mechanism of ovulation is complex. The processes of fertilization and ovulation are described in this report. Information includes a description of the natural indicators of fertility and infertility, the cervical mucus pattern, and the Guidelines for the Billings Ovulation Method. The ovarian monitor which provides for the measurement of ovarian hormones (estrone glucuronide (EIG) and pregnanediol glucuronide (PdG) in a timed specimen of urine is also described. The cervical mucus pattern method measures ovarian hormones and fertility. No more than 2% of women who have been taught the Ovulation Method and performed the charting would need to use the Ovarian Monitor. It is commonly used to assure that the women's observations and interpretations are correct when there is a strong desire to either achieve or postpone pregnancy. For research, the monitor is useful in accurately measuring the timing of ovulation within the phase of potential fertility during the cycle and the changing probabilities of conception on days within the fertile period. The limits of the fertilizing life span of sperm can be measured as well as the factors which influence this life span. The day of maximum fertility, the correlation of the mucus pattern with fertility and time of ovulation, and assessment of conception cycles are measurable. Diagnostic information can be gleaned which will help to explain bleeding patterns, particularly around menopause, where fluctuating ovarian hormonal levels influence unexplained bleeding patterns. The Monitor can be useful as a test for pregnancy in measurement of high PdG and E1G levels. Four phases are identified for interpreting the ovulatory cycle: 1) the E1G and PdG levels are declining during the beginning of menstruation to reach a constant level (20-60 nmol/24 hours and .9 - 3.3 mcmol/24 hours); 2) rising E1G values and low PdG values and changing mucus pattern of the preovulatory cycle; 3) the ovulatory phase of peak E1G values (150-450 nmol/24 hours) followed by a distinct fall and the beginning of a rise in PdG values and the Peak of the mucus pattern; and 4) the luteal phase of rising PdG (9-36 mcmol/24 hours), and rising E1G values (100-400 nmol/24 hours) to maximum, and then falling before menstruation.
PMID 1746210 1746210 Billings et al. 1991, Billings 1991
Cite this article
Billings, J. J. (1991). The validation of the Billings ovulation method by laboratory research and field trials. Acta Europaea fertilitatis, 22(1), 9-15.
Billings JJ. The validation of the Billings ovulation method by laboratory research and field trials. Acta Eur Fertil. 1991;22(1):9-15.
Billings, J. J. "The validation of the Billings ovulation method by laboratory research and field trials." Acta Europaea fertilitatis, vol. 22, no. 1, 1991, pp. 9-15.
Natural family planning (NFP) is based on the knowledge *largely nonexistent) of a women as to whether she is in her fertile period or not. In contrast to the calendar method, the Billings method consists of observing bodily functions, whereby women learn about the fertile and infertile period during the menstrual cycle. This method is very safe as long as the woman has been instructed thoroughly. The Pearl index (the number of pregnancies/100 woman years) can be 1. In a Swedish province, 7/1000 population used this method and had an abortion rate of .5/1000, a fact contradicting the allegation of mass abortion as a result of the method. Only well-trained NFP instructors can teach women, and at the University of Umea such training has been available for some years. The biological basis of the Billings method rests on the fact that every release of an egg is preceded by a ripening process of a follicle in the ovary. This follicle secretes increasing amounts of estrogen which stimulates the cervix to produce secretions for the sperm. Right before ovulation, the follicle reduces estrogen production and noradrenaline takes over, stimulating the peak-day secretion (P-secretion) for further selection of sperm. Ovulation usually occurs on the peak day, which is the day of maximum fertility and the last day of mucous symptoms. For 3 days after peak day until menstruation, the risk of becoming pregnant diminishes successively until it is as low as after sterilization. The instructor is trained to recognize and overcome certain factors that make it more difficult to identify the mucous symptoms, such as the previous use of oral contraceptives, certain illnesses, drugs, and life styles. NFP can also be used for attaining pregnancy by identifying the peak day; women with premenstrual syndrome can calculate when their symptoms start, and sportswomen can predict the time of their menstruation. NFP is fascinating when it is compared to other methods because of its human dimension, and there is still a great deal to be learned about it.
Fehring RJ, 1990·J Obstet Gynecol Neonatal Nurs·
Open Access
Time of ovulation as detected by a self-test of luteinizing hormone (LH) in the urine was compared with time of ovulation as detected by self-observation of cervical mucus. Twenty regularly cycling women monitored their cervical mucus and urine LH for two complete menstrual cycles. Of the cycles that had an LH surge, 100% were on the peak day of cervical mucus or within three days before the peak day. Self-observation of cervical mucus, therefore, can be an accurate method of determining optimal fertility.
What is the normal range of cervical mucus patterns and number of days with high or moderate day-specific probability of pregnancy (if intercourse occurs on a specific day) based on cervical mucus secretion, in women without known subfertility, and how are these patterns related to parity and age? The mean days of peak type (estrogenic) mucus per cycle was 6.4, the mean number of potentially fertile days was 12.1; parous versus nulliparous, and younger nulliparous (<30 years) versus older nulliparous women had more days of peak type mucus, and more potentially fertile days in each cycle. The rise in estrogen prior to ovulation supports the secretion of increasing quantity and estrogenic quality of cervical mucus, and the subsequent rise in progesterone after ovulation causes an abrupt decrease in mucus secretion. Cervical mucus secretion on each day correlates highly with the probability of pregnancy if intercourse occurs on that day, and overall cervical mucus quality for the cycle correlates with cycle fecundability. No prior studies have described parity and age jointly in relation to cervical mucus patterns. STUDY DESIGN, SIZE, This study is a secondary data analysis, combining data from three cohorts of women: 'Creighton Model MultiCenter Fecundability Study' (CMFS: retrospective cohort, 1990-1996), 'Time to Pregnancy in Normal Fertility' (TTP: randomized trial, 2003-2006), and 'Creighton Model Effectiveness, Intentions, and Behaviors Assessment' (CEIBA: prospective cohort, 2009-2013). We evaluated cervical mucus patterns and estimated fertile window in 2488 ovulatory cycles of 528 women, followed for up to 1 year. PARTICIPANTS/MATERIALS, SETTING, Participants were US or Canadian women age 18-40 years, not pregnant, and without any known subfertility. Women were trained to use a standardized protocol (the Creighton Model) for daily vulvar observation, description, and recording of cervical mucus. The mucus peak day (the last day of estrogenic quality mucus) was used as the estimated day of ovulation. We conducted dichotomous stratified analyses for cervical mucus patterns by age, parity, race, recent oral contraceptive use (within 60 days), partial breast feeding, alcohol, and smoking. Focusing on the clinical characteristics most correlated to cervical mucus patterns, linear mixed models were used to assess continuous cervical mucus parameters and generalized linear models using Poisson regression with robust variance were used to assess dichotomous outcomes, stratifying by women's parity and age, while adjusting for recent oral contraceptive use and breast feeding. MAIN The majority of women were <30 years of age (75.4%) (median 27; IQR 24-29), non-Hispanic white (88.1%), with high socioeconomic indicators, and nulliparous (70.8%). The mean (SD) days of estrogenic (peak type) mucus per cycle (a conservative indicator of the fertile window) was 6.4 (4.2) days (median 6; IQR 4-8). The mean (SD) number of any potentially fertile days (a broader clinical indicator of the fertile window) was 12.1 (5.4) days (median 11; IQR 9-14). Taking into account recent oral contraceptive use and breastfeeding, nulliparous women age ≥30 years compared to nulliparous women age <30 years had fewer mean days of peak type mucus per cycle (5.3 versus 6.4 days, P = 0.02), and fewer potentially fertile days (11.8 versus 13.9 days, P < 0.01). Compared to nulliparous women age <30 years, the likelihood of cycles with peak type mucus ≤2 days, potentially fertile days ≤9, and cervical mucus cycle score (for estrogenic quality of mucus) ≤5.0 were significantly higher among nulliparous women age ≥30 years, 1.90 (95% confidence interval (CI) 1.18, 3.06); 1.46 (95% CI 1.12, 1.91); and 1.45 (95% CI 1.03, 2.05), respectively. Between parous women, there was little difference in mucus parameters by age. Thresholds set a priori for within-woman variability of cervical mucus parameters by cycle were examined as follows: most minus fewest days of peak type mucus >3 days (exceeded by 72% of women), most minus fewest days of non-peak type mucus >4 days (exceeded by 54% of women), greatest minus least cervical mucus cycle score >4.0 (exceeded by 73% of women), and most minus fewest potentially fertile days >8 days (found in 50% of women). Race did not have any association with cervical mucus parameters. Recent oral contraceptive use was associated with reduced cervical mucus cycle score and partial breast feeding was associated with a higher number of days of mucus (both peak type and non-peak type), consistent with prior research. Among the women for whom data were available (CEIBA and TTP), alcohol and tobacco use had minimal impact on cervical mucus parameters. LIMITATIONS, We did not have data on some factors that may impact ovulation, hormone levels, and mucus secretion, such as physical activity and body mass index. We cannot exclude the possibility that some women had unknown subfertility or undiagnosed gynecologic disorders. Only 27 women were age 35 or older. Our study participants were geographically dispersed but relatively homogeneous with regard to race, ethnicity, income, and educational level, which may limit the generalizability of the findings. Patterns of cervical mucus secretion observed by women are an indicator of fecundity and the fertile window that are consistent with the known associations of age and parity with fecundity. The number of potentially fertile days (12 days) is likely greater than commonly assumed, while the number of days of highly estrogenic mucus (and higher probability of pregnancy) correlates with prior identifications of the fertile window (6 days). There may be substantial variability in fecundability between cycles for the same woman. Future work can use cervical mucus secretion as an indicator of fecundity and should investigate the distribution of similar cycle parameters in women with various reproductive or gynecologic pathologies. STUDY FUNDING/COMPETING INTEREST(S): Funding for the three cohorts analyzed was provided by the Robert Wood Johnson Foundation (CMFS), the Eunice Kennedy Shriver National Institute of Child Health and Human Development (TTP), and the Office of Family Planning, Office of Population Affairs, Health and Human Services (CEIBA). The authors declare that they have no conflict of interest. N/A.
Porucznik CA et al., 2014·BMC Womens Health·
Open Access
Transient exposures may influence fertility and early embryonic development. To assess the time of conception in vivo and conduct concurrent biomonitoring, ovulation must be identified prospectively. We report on the development and validation of a simple, prospective method, the Peak Day method, to determine likely day of ovulation based upon daily observations of cervical fluid. We recruited 98 women to learn the Peak Day method from a brochure, 26 of whom concurrently used the method with blinded daily urine hormone monitoring (estrone glucuronide and luteinizing hormone). All women were instructed to complete an exposure questionnaire immediately upon identifying ovulation. Briefly, the exposure questionnaire captured time-varying and transient exposures such as medication use, water consumption, and amount of sleep. We assessed timely completion of the exposure questionnaire, agreement of women's estimated day of ovulation (EDO) and the EDO by expert review, and agreement between the EDO by expert review and by blinded urine monitoring. Of 147 cycles evaluated, women selected an EDO in 130 (88%) and subsequently completed the periovulatory exposure questionnaire in 122 (94%) cycles. Of the 26 cycles evaluated with blinded hormonal monitoring, the Peak Day "best quality" algorithm, based upon cervical fluid, identified ovulation ± 3 days of the urine monitor in 24 cycles (92%). With simple written instructions, women can identify an estimated day of ovulation and perform periovulatory exposure assessment. The Peak Day method is highly cost-effective and could be applied by researchers to target periconceptional or very early developmental stage exposure assessment.