The Medical and Surgical Practice of NaProTECHNOLOGY, 643-652, 2004
Chapter 48: Fecundity and Mucus Cycle Score
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- University of Utah ROR
The Medical and Surgical Practice of NaProTECHNOLOGY, 643-652, 2004
The Mucus Cycle Score, derived from the standardized CrMS daily observations, quantifies cervical mucus quality and quantity across a cycle and correlates with measured estrogen levels and fecundity rates, providing a non-invasive index of reproductive potential. Declining mucus scores are clinically actionable, directing investigation into hypoestrogenism, cervical pathology, or medication effects that reduce cycle fecundity and can be corrected before ART is considered.
Stanford, J. B. (2004). Chapter 48: Fecundity and Mucus Cycle Score. The Medical and Surgical Practice of NaProTECHNOLOGY, 643-652.
Stanford JB. Chapter 48: Fecundity and Mucus Cycle Score. The Medical and Surgical Practice of NaProTECHNOLOGY. 2004:643-652.
Lora J et al., 2022 · Clin. Exp. Obstet. Gynecol. · Open Access
The principal objective of this study was to correlate biophysical properties of vaginal discharge present in the cervical mucus with the timing of the fertile window. In particular, we produce measures of the viscoelasticity of the cervical secretion using two methods. The first uses only the elasticity extracted from the Creighton Model Fertility Care System (CrMs) scale, calculated P-6 ovulation estimated day (OED) with respect to the peak day of the CrMs. The second uses a numerical method that takes into account the changes in viscoelasticity, but without reference to the peak day calculated using the CrMs model. Using both methods, twelve records were obtained from a single female subject. The methodology used to evaluate the viscoelasticity factor was by measuring the approximate length in centimeters (cm) of the vaginal discharge of cervical discharge. For this, the scale of the stretching graph established by observing the stretching of CrMS was used, taking into account the previous 6 days at peak day P-6. The first method, which we termed CFW (Clinical Fertile Window), uses a measure based on the approximate length (cm) of the maximal stretchiness of the vaginal discharge. The second method we termed SFW (Software-CrMS/strectching) (Software-based Fertile Window). The fertile window was detected correctly in 100% of the cases using either method, and a correlation value of 0.71 was observed between the two methods. We conclude that the assessment of viscoelasticity using SFW algorithm allowed in this pilot study to detect the fertile window and to describe the evolution pattern of cervical discharge throughout the fertile window. Our study provides support for the use of computational methods in detecting the fertile window, taking only into account the time evolution of the cervical discharge throughout the menstrual cycle.
Billings JJ, 1981 · Int J Fertil ·
The ovulation method provides a woman with an awareness of her cervical mucus pattern. This enables her to mark the beginning and end of the fertile phase of the cycle as well as the time of maximum fertility. Not only is the time of ovulation located but also there is recognition of infertility in the absence of ovulation. The key to understanding is the concept of the basic infertile pattern which precedes the commencement of follicular development; the key to successful use is competent teaching. After preliminary considerations on the fertile phase the determination of ovulation and the aspect of periodic abstinence two basic studies comparing clinical and hormonal observations are reviewed showing how accurately the cervical mucus reflects ovarian activity. Understanding the basic infertile pattern and the two sets of rules (the early day rules and peak rule identifying respectively the beginning and end of the fertile period) is basic to the application of the ovulation method. Criteria for the ideal family planning method and the importance of quality teaching are presented. Two problems requiring attention in NFP are restrictive terminology in data collection and a lack of fully developed and positive approach to periodic abstinence.
Stein IF Sr et al., 1952 · Fertil Steril ·
Accurate timing of ovulation is especially necessary (1) in artificial insemination in order to avoid wastage of donor semen; (2) in cases where the husband is relatively infertile and it is necessary to conserve his semen. While many physicians rely upon the basal body temperature curve for timing ovulation, the interpretation of such curves is varied. Some physicians believe ovulation occurs prior to the lowest point in the temperature cycle, while others believe that ovulation occurs either at the low point or following the thermal shift. We have been disappointed in our ability to interpret the basal body temperature curve for accurate timing of ovulation, and have placed greater reliance upon concurrent phenomena, such as changes in the quantity and viscosity of cervical mucus and the cyclic changes observed in the vaginal smear. Although the relationship between the occurrence of a profuse, thin cervical mucus discharge and the optimal time of fertility in the human has been recognized for the past century, in our opinion this relationship requires further evaluation. In his excellent review, "Cervical mucus: Cyclic variations and their clinical significance," Shettles quotes Robin who, in 1848, noted the viscous nature of human cervical secretions; and Smith who, in 1865, concluded that conception is most likely when the mucus contents of the cervix are in the most fluid condition. J. Marion Sims, who invented a vaginal speculum and first described the postcoital examination in 1868, observed that the test is positive for motile spermatozoa when the cervical mucus becomes clear and translucent, and about the consistency of the white of egg. Although these observations on human cervical mucus have been well documented, they have been almost disregarded by gynecologists. The significance of the cyclical outpouring of cervical mucus has been rediscovered in the past few years and has aroused great interest in students of sterility. The optimal time of fertility in domestic animals is the period of heat or estrus. In 1925, Woodman and Hammond showed that during estrus, bovine cervical mucus is fluid and capable of being drawn out into threads, whereas in diestrus the mucus is thick. Seguy and Vimeux, and Seguy and Simonnet called attention to the optimal conditions of longevity of human spermatozoa in the fluid, glairy mucus of the cervix at midcycle. They postulated that these changes in cervical mucus were associated with ovulation and could be compared to the period of estrus in subprimate mammals. They correlated these changes with visual evidence of ovulation at laparotomy. Subject: ively, many women observe an increased sticky, mucoid discharge which is typical at midcycle and which is present over a period of days. On occasion this discharge is blood-tinged and may be compared to the distinct bloody mucoid discharge present in the domestic animal "in heat." This mucus can be seen exuding from the cervix at midcycle and it may be aspirated from the endocervix and actually weighed, as reported by Viergiver and Pommerenke. Clift demonstrated certain rheologic properties of cervical mucus, especially flow elasticity and Spinnbarkeit. Flow elasticity, or elastic recoil of mucus, is measured by an instrument described by Blair. The use of the Blair capillary viscometer is a cumbersome method which we discontinued. We have had no experience with the new modification of the viscometer described by Clift, Glover, and Blair. Spinnbarkeit is easily tested, and we have found it to be a very practical objective method for determining viscosity of cervical mucus. In performing this test (Fig. 1), a vaginal speculum is inserted, exposing the cervix. A glass cannula is inserted into the endocervix and by means of gentle suction, a quantity of endocervical mucus is obtained. This mucus is blown onto a glass slide and a cover slip is placed on it. The mucus adheres to both the slide and the cover slip, and by withdrawing the cover slip, a thread of mucus is formed which can be measured in centimeters (Fig. 2). Usually, the cover slip is withdrawn several times, and the average length of the thread is ascertained. It is our purpose to show the relationship of Spinnbarkeit to other cyclic phenomena occurring during the menstrual cycle, such as basal body temperatures, vaginal smears, quantity of cervical mucus, and longevity of spermatozoa (Fig. 3).
Hilgers TW, 2004 · The Medical and Surgical Practice of NaProTECHNOLOGY ·
CrMS charting features -- Peak day definition, pre-Peak mucus quality and duration, post-Peak phase length, and premenstrual spotting -- are systematically compared against sonographic and endocrine findings to demonstrate that prospective cycle observations reliably identify specific ovulation disorder categories. This clinical validation shows that the CrMS chart functions as a non-invasive biomarker map capable of directing targeted ultrasound and hormonal investigation, and that treatment guided by the classification improves ovulatory and fertility outcomes.