Digital fertility awareness-based contraception offers an alternative choice for women who do not wish to use hormonal or invasive methods. The aim of this study was to investigate the key demographics of current users of the Natural Cycles app and assess the contraceptive outcomes of women preventing pregnancy in a UK cohort of women.
Materials and Methods
This was a real world observational prospective observational study. The typical-use effectiveness of the method was calculated using both 13-cycle cumulative probability of pregnancy (life table analysis) and Pearl Index for the entire study cohort. Perfect-use PI was calculated using data from cycles where sexual intercourse during the fertile window was marked as protected and no unprotected sex was recorded on fertile days.
Results
12,247 women were included in the study and contributed an average of 9.9 months of data for a total of 10,066 woman years of exposure. The mean age of the cohort was 30, mean BMI 23.4, the majority were in a stable relationship (83.2%) and had a university degree or higher (83%). The one year typical use, PI was 6.1 (95% CI: 5.6, 6.6) and with perfect-use was 2.0 (95% CI: 1.3, 2.8). 13 cycle pregnancy probability was 7.1%.
Conclusions
This is the first study which describes the use of a digital contraceptive by women in the UK. It describes the demographics of users and how they correlate with the apps effectiveness at preventing pregnancy.
Natural Cycles app contraceptive effectiveness UK cohort, digital fertility awareness contraception Pearl Index, Natural Cycles typical use perfect use pregnancy rate, fertility awareness-based method app real world effectiveness, digital contraception demographic analysis UK women, Natural Cycles 13 cycle cumulative pregnancy probability, smartphone fertility app contraceptive outcomes prospective study, non-hormonal contraception digital fertility tracking effectiveness, Scherwitzl Natural Cycles observational study, fertility awareness app life table analysis pregnancy risk
PMID 33539252 33539252 DOI 10.1080/13625187.2020.1867844 10.1080/13625187.2020.1867844 Pearson et al. 2021, Pearson 2021
Cite this article
Pearson, J. T., Chelstowska, M., Rowland, S. P., Mcilwaine, E., Benhar, E., Berglund Scherwitzl, E., Walker, S., Gemzell Danielsson, K., & Scherwitzl, R. (2021). Natural Cycles app: contraceptive outcomes and demographic analysis of UK users. The European journal of contraception & reproductive health care : the official journal of the European Society of Contraception, 26(2), 105-110. https://doi.org/10.1080/13625187.2020.1867844
Pearson JT, Chelstowska M, Rowland SP, Mcilwaine E, Benhar E, Berglund Scherwitzl E, et al. Natural Cycles app: contraceptive outcomes and demographic analysis of UK users. Eur J Contracept Reprod Health Care. 2021;26(2):105-110. doi:10.1080/13625187.2020.1867844
Pearson, J. T., et al. "Natural Cycles app: contraceptive outcomes and demographic analysis of UK users." The European journal of contraception & reproductive health care : the official journal of the European Society of Contraception, vol. 26, no. 2, 2021, pp. 105-110.
Keywords
Contraceptive Agents
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