The (PD) peak day of cervical mucus is an important biologic marker for the self-determination of the optimal time of fertility in a woman's menstrual cycle. The purpose of this article is to provide evidence (literature and empiric) for the accuracy of the PD of cervical mucus as a biologic marker of peak fertility and the estimated day of ovulation. An analysis of data from four published studies that compared the self-determination of the PD of cervical mucus with the urinary luteinizing hormone (LH) surge was conducted. The four studies yielded 108 menstrual cycle charts from 53 women participants. The 108 cycles ranged in length from 22 to 75 days (mean 29.4 SD 6.0). Ninety-three of the 108 cycles had both an identified PD and LH surge. Data charts showed that 97.8% of the PD fell within +/-4 days of the estimated day of ovulation. Use of a standardized mucus cycle scoring system indicated that the peak in cervical mucus ratings was highest on the day of the LH surge. Self-determination of the PD of cervical mucus is a very accurate means of determining peak fertility and a fairly accurate means of determining the day of ovulation and the beginning of the end of the fertile time.
PMID 12413617 12413617 DOI 10.1016/s0010-7824(02)00355-4 10.1016/s0010-7824(02)00355-4
Cite this article
Fehring, R. J. (2002). Accuracy of the peak day of cervical mucus as a biological marker of fertility. Contraception, 66(4), 231-235. https://doi.org/10.1016/s0010-7824(02)00355-4
Fehring RJ. Accuracy of the peak day of cervical mucus as a biological marker of fertility. Contraception. 2002;66(4):231-235. doi:10.1016/s0010-7824(02)00355-4
Fehring, R. J. "Accuracy of the peak day of cervical mucus as a biological marker of fertility." Contraception, vol. 66, no. 4, 2002, pp. 231-235.
To examine trends in national reporting of broken intrauterine devices (IUDs). We enumerated IUD device "breakage" reports in the Food and Drug Administration Adverse Event Reporting System from inception (1998) until February 2022. We explored associations of breakage with IUD type (copper versus hormonal), year reported, reporter (consumer versus clinician), and patient characteristics (age and weight). We identified 4144 breakage reports for copper versus 2140 for hormonal IUDs. Among the 170,215 adverse events reported, breaks were disproportionately reported for copper (9.6%) versus hormonal (1.7%) IUDs. National pharmacovigilance data suggests disproportionate breakage in copper versus hormonal IUDs though the true prevalence of breaks cannot be calculated from this dataset.
Contraception/ComparisonEfficacyNovel FormulationsPooled Analysis
Open Access
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Fertility AwarenessApp ComparisonFertile Window IdentificationBBT and Cervical Mucus
The Natural Cycles app employs daily basal body temperature to define the fertile window via a proprietary algorithm and is clinically established effective in preventing pregnancy. We sought to (1) compare the app-defined fertile window of Natural Cycles to that of CycleProGo, an app that uses BBT and cervical mucus to define the fertile window and (2) compare the app-defined fertile windows to the estimated physiologic fertile window. Daily BBT were entered into Natural Cycles from 20 randomly selected regularly cycling women with at least 12 complete cycles from the CycleProGo database. The proportion of cycles with equivalent (±1 cycle day) fertile-window starts and fertile-window ends was determined. The app-defined fertile windows were then compared to the estimated physiologic fertile window using Peak mucus to estimate ovulation. Fifty seven percent of cycles (136/238) had equivalent fertile-window starts and 36% (72/181) had equivalent fertile-window end days. The mean overall fertile-window length from Natural Cycles was 12.8 days compared to 15.1 days for CycleProGo (p < 0.001). The Natural Cycles algorithm declared 12% to 30% of cycles with a fertile-window start and 13% to 38% of cycles with a fertile-window end within the estimated physiologic fertile window. The CycleProGo algorithm declared 4% to 14% of cycles with a fertile-window start and no cycles with a fertile-window end within the estimated physiologic fertile window. Natural Cycles designated a higher proportion of cycles days as infertile within the estimated physiologic fertile window than CycleProGo.
Use of cervical mucus in addition to BBT may improve the accuracy of identifying the fertile window. Additional studies with other markers of ovulation and the fertile window would give additional insight into the clinical implications of app-defined fertile window differences.