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Fertility Awareness Effectiveness

Identification and prediction of the fertile window using NaturalCycles

Berglund Scherwitzl E, Lindén Hirschberg A, Scherwitzl R

The European journal of contraception & reproductive health care : the official journal of the European Society of Contraception, 20(5), 403-8, 2015
DOI 10.3109/13625187.2014.988210 PMID 25592280

Abstract

Objectives

The aim of the study was to evaluate the ability of a novel web and mobile application to identify a woman's ovulation day and fertile window, in order to use it as a method of natural birth control.

Methods

A retrospective study was performed on 1501 cycles of 317 women aged 18 to 39 years. Women entered their basal body temperatures, ovulation test results and date of menstruation into the application.

Results

The mean delay from the first positive ovulation test to the temperature-based estimation of the ovulation day was 1.9 days; the length of the luteal phase varied on average by 1.25 days per user. Only 0.05% of non-fertile days were falsely attributed and found within the fertile window.

Conclusions

The method is effective at identifying a user's ovulation day and fertile window and can therefore be used as a natural method of birth control.

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Related research

Fertility Awareness › Effectiveness › Fertile Window Estimation · Menstrual Cycle › Cycle Biomarkers › Basal Body Temperature
Angelica Lindén Hirschberg
A Hirschberg
PMID 25592280 25592280 DOI 10.3109/13625187.2014.988210 10.3109/13625187.2014.988210 Berglund Scherwitzl et al. 2015, Berglund Scherwitzl 2015

Keywords

Basal body temperature, Fertile window, Fertility awareness, Fertility monitor, Natural birth control, Natural family planning

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