The Creighton Model FertilityCare™ System (CrMS) is the only natural method of family planning developed by an OB/Gyn.  It is based on observing cervical secretions throughout a woman’s cycle. During the fertile period of ovulation cervical crypts respond to rising estrogen levels, producing a type of mucus that aids the motility and lifespan of sperm. This mucus is necessary for conception to take place.  Conversely, the absence of cervical mucus indicates periods of infertility.  Thus, like all natural methods, it can be used as a method to achieve, as well as avoid, pregnancy.


How the CrMS works:

PLEASE NOTE: by no means is the following sufficient detail to substitute for the private instruction in the CrMS.  Every woman is different, and instruction is specific to her particular mucus pattern, including continuous mucus.


The woman is instructed to observe her cervical mucus every day, every  time she goes to the bathroom, both before and after urination and/or a bowel movement. She is taught to first determine the sensation the mucus creates (dry, smooth, or lubricative) as she passes the tissue over the perineum, then to observe the tissue for any mucus present.  If mucus is present she will finger test, noting the degree of stretch and it’s color. As ovulation nears the cervical mucus becomes increasingly clear, stretchy and/or lubricative.  After ovulation there is an abrupt change, where all three mucus qualities, clear, stretchy (an inch or more) and lubricative, are absent.  The last day she observes mucus that is clear, stretches one inch or more, and/or is lubricative, is her Peak Day.  Because ovulations can occur up to three days after the Peak Day the next three days are also indicated as fertile. By these mucus observations the couple is able to pinpoint their days of fertility and infertility, and plan sexual intercourse based on their intentions to achieve or avoid a pregnancy.

Trying to Avoid:

When a couple is avoiding pregnancy, intercourse is at the end of the day on dry days in the pre-ovulatory phase of the cycle.  By waiting until the end of the day they are able to confirm the absence of mucus, and thus infertility of that day.  In the post-ovulatory phase, intercourse can be any time of day, as ovulation has passed.


Trying to Achieve:

When trying to achieve pregnancy the couple just flips the instructions. They will use days when mucus is present, with the best chances of conception occurring when the mucus is clear, stretchy and/or lubricative.


Women with irregular cycles (those that don’t fall in the 21-38 day window) use the Creighton model with equally as high effectiveness as women with regular cycles. In fact, charting with the CrMS can help your NaPro doctor detect problems that may be causing your cycle to fall outside of the normal range. CrMS charting can help diagnose underlying gynecological problems that might otherwise go unnoticed, or be masked if she is prescribed oral contraceptives for the symptoms.

Does it work?

You bet. As well as hormonal contraceptives? Yes, and even better.  In a study with 1,876 couples, and over 17,130 couple months the method effectiveness (perfect use) for avoiding a pregnancy was 99.5% after one year. The use effectiveness (typical use) was 96.8%. The Pill (combined oral contraceptive pills) has method effectiveness rates and use effectiveness rates of 99.7% and ranging from 92-98%, respectively.


For those having trouble conceiving, the CrMS in conjunction with the new medical approach of NaProTECHNOLOGY®,  is considerably more effective than IVF.  NaPro corrects the underlying cause of infertility and allows the couple to conceive with a natural act of intercourse.  To find a physician trained in NaProTECHNOLOGY® near you, look under “Find a Medical Consultant” at