Creighton Model FertilityCare System (CrMS)

By RRM Academy Reviewed by Dr. Naomi Whittaker, MD, Board-Certified OBGYN, MIGS, NFPMC, FCI Updated May 7, 2026

A standardized, prospective method of Natural Family Planning (NFP) focused on detailed observation and classification of cervical mucus patterns and other biological markers, developed at the Pope Paul VI Institute by Dr. Thomas Hilgers. The CrMS is distinct from the broader FABM category. Its developers specifically distinguish it as an NFP method. The CrMS provides precise information for monitoring gynecologic health and fertility and forms the diagnostic foundation for NaProTECHNOLOGY, allowing cycle-phase-specific timing of blood tests and medical treatments. Published effectiveness data show CrMS is up to 98% effective for achieving pregnancy in couples with normal fertility and, in conjunction with NaPro, up to 80% effective for couples experiencing infertility. A prospective cohort study (CEIBA) in 17 CrMS centers across the USA and Canada found the highest 13-cycle pregnancy rate with correct use to conceive was 89.6%, when intercourse was timed to peak-type mucus days.⁷⁸⁹

This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.