The purpose of this study was to compare the fertile phase of the menstrual cycle as determined by the Clearplan Easy Fertility Monitor (CPEFM) with self-monitoring of cervical mucus. One-hundred women (mean age = 29.4 years) observed their cervical mucus and monitored their urine for estrogen and luteinizing hormone metabolites with the CPEFM on a daily basis for 2-6 cycles and generated 378 cycles of data; of these, 347 (92%) had a CPEFM peak. The beginning of the fertile window was, on average, day 11.8 (SD = 3.4) by the monitor and day 9.9 (SD = 3.0) by cervical mucus (r = 0.43, p < 0.001). The average first day of peak fertility by the monitor was 16.5 (SD = 3.6) and by cervical mucus 16.3 (SD = 3.7) (r = 0.85, p < 0.001). The mean length of the fertile phase by the monitor was 7.7 days (SD = 3.1) and by cervical mucus 10.9 days (SD = 3.7) (t = 12.7, p < 0.001). The peak in fertility as determined by the monitor and by self-assessment of cervical mucus is similar but the monitor tends to underestimate and self-assessment of cervical mucus tends to overestimate the actual fertile phase.
PMID 14720613 14720613 DOI 10.1016/j.contraception.2003.09.011 10.1016/j.contraception.2003.09.011
Cite this article
Fehring, R. J., Raviele, K., & Schneider, M. (2004). A comparison of the fertile phase as determined by the Clearplan Easy Fertility Monitor and self-assessment of cervical mucus. Contraception, 69(1), 9-14. https://doi.org/10.1016/j.contraception.2003.09.011
Fehring RJ, Raviele K, Schneider M. A comparison of the fertile phase as determined by the Clearplan Easy Fertility Monitor and self-assessment of cervical mucus. Contraception. 2004;69(1):9-14. doi:10.1016/j.contraception.2003.09.011
Fehring, R. J., et al. "A comparison of the fertile phase as determined by the Clearplan Easy Fertility Monitor and self-assessment of cervical mucus." Contraception, vol. 69, no. 1, 2004, pp. 9-14.
Keywords
Estrogens, Luteinizing Hormone
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