The Medical and Surgical Practice of NaProTECHNOLOGY, 129-153, 2004
Chapter 6: Introductory Presentation of the CrMS
Thomas W Hilgers
Author affiliations
Pope Paul VI Institute for the Study of Human Reproduction, Omaha, Nebraska.ROR
Abstract
This 2004 textbook chapter by Thomas W. Hilgers outlines the structure and content of the formal introductory session used to enroll couples in the Creighton Model FertilityCare System (CrMS). It covers the biological foundation of fertility charting, the role of cervical mucus as a biomarker of the reproductive cycle, and the educational framework designed to train couples in systematic, real-time cycle observation.
what is the Creighton Model introductory session, how does cervical mucus indicate fertility, what does NaProTECHNOLOGY teach couples about the cycle, how effective is the Creighton Model for avoiding pregnancy, what is Peak Day in the Creighton Model, how does progesterone affect cervical mucus, can fertility charting help identify hormone problems, how do couples use the Creighton Model to get pregnant, what is the biological valve in cervical mucus research
Hilgers et al. 2004, Hilgers 2004
Cite this article
Hilgers, T. W. (2004). Chapter 6: Introductory Presentation of the CrMS. The Medical and Surgical Practice of NaProTECHNOLOGY, 129-153.
Hilgers TW. Chapter 6: Introductory Presentation of the CrMS. The Medical and Surgical Practice of NaProTECHNOLOGY. 2004:129-153.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
The Creighton Model FertilityCare System (CrMS) is introduced as a standardized, scientifically grounded method for observing and recording cervical mucus biomarkers and bleeding patterns across the menstrual cycle. Its development from earlier natural family planning methods into a fully systematized fertility monitoring tool is traced, establishing the CrMS as the observational substrate for all subsequent NaProTECHNOLOGY medical applications.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
The CREIGHTON MODEL FertilityCare System (CrMS) rests on a decades-long body of research demonstrating that cervical mucus functions as a physiologically regulated biological valve, opening predictably at the periovulatory estrogen rise and closing in the post-Peak phase. Chapter 15 of Hilgers (2004) synthesizes hormonal, ultrasound, cytologic, and biophysical evidence to establish that a woman's external observation of her Peak Day reliably identifies the fertile window, and documents the system's effectiveness data for both achieving and avoiding pregnancy across a five-study meta-analysis of nearly 1,900 couples.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
The content and sequence of the introductory and follow-up instructional sessions that constitute the formal CrMS education series are outlined, covering observation technique, recording conventions, and the practitioner-client interaction model. Consistent delivery of these core instructions establishes the behavioral competence required for both family planning use and the medical monitoring applications that NaProTECHNOLOGY depends upon.
Hilgers TW, 2004·The Medical and Surgical Practice of NaProTECHNOLOGY·
NaProTECHNOLOGY uses the Peak Day of the Creighton Model chart — the last day of the most fertile-type cervical mucus — as the reference point for dating conception, providing a biologically grounded alternative to last menstrual period dating that remains accurate across irregular cycles. Precise cycle-based dating improves the clinical interpretation of early pregnancy hormone levels, ultrasound findings, and obstetric gestational age assignments, reducing unnecessary interventions triggered by apparent growth discordance.