New study into role of Natural Cycles in ‘Plan a Pregnancy’ mode

The Freyja study aims to improve understanding of how technologies like Natural Cycles are used by women and their partners when trying to conceive.

STOCKHOLM, 30 January 2019 – Natural Cycles today announced that the London School of Hygiene & Tropical Medicine (LSHTM) in collaboration with the University of Plymouth, have initiated the Freyja study – an independent study to explore the views and experiences of people who currently use, or have previously used, the Natural Cycles app in ‘Plan a Pregnancy’ mode.

Natural Cycles uses a smart algorithm that is sensitive to subtle patterns in a woman’s cycle to determine daily fertility; it does this by analysing changes in basal body temperature, which increases after ovulation. To use Natural Cycles, women take their temperature with a basal thermometer first thing in the morning and enter the reading into the app at least 5 times a week, as well as adding their period dates each month.

The Natural Cycles algorithm analyses this data to predict the fertile window (around 6 days per cycle), which can help women to increase their chances of becoming pregnant. For example, while the likelihood of conceiving is negligible after ovulation, for healthy women this increases to 10% if they have intercourse five days before ovulation and to 33% if they have intercourse on the day of ovulation.1

There has been a growing interest in using online and app-based methods like Natural Cycles to monitor daily fertility: in a recent survey of over 1,000 women in the UK, 35% reported that they used a fertility tracking app at least once a month.2 However, this area has received limited research attention to-date. In this qualitative study, researchers will interview women who use Natural Cycles themselves and the partners of those who do so, to explore their respective experience using the Natural Cycles app and other fertility-awareness based methods when trying to conceive.

Dr Simon Rowland, Head of Medical Affairs at Natural Cycles, said: “We are delighted to be supporting this independent collaboration between the London School of Hygiene & Tropical Medicine and the University of Plymouth, and we very much look forward to seeing the results. At Natural Cycles, our mission is to pioneer women’s health with research and passion, so that every woman is empowered with the knowledge she needs to take charge of her own health. We hope that the insights generated by the Freyja study will help in advancing these efforts and in building our understanding of how the Natural Cycles app can support women who are trying to conceive.

If you would like to read more about the Freyja study, please visit:

About the Freyja study

The Freyja Study was named after Freyja, the Norse Goddess of Fertility who is said to have originated from South Sweden.

This study is funded by Natural Cycles. It is being conducted independently by researchers at the London School of Hygiene and Tropical Medicine (LSHTM) and the University of Plymouth, and is steered by an independent advisory group.

About Natural Cycles

Natural Cycles was founded in June 2013 by former CERN physicist, Dr Elina Berglund and her husband Dr Raoul Scherwitzl, who also has a background in physics. Natural Cycles is an effective, natural method of contraception that is delivered in the form of an app. It uses a smart algorithm that is sensitive to subtle patterns in a woman’s cycle to determine daily fertility, based on basal body temperature and period data. Natural Cycles is 93% effective with typical use,3 which means that 7 women out of 100 get pregnant during 1 year of use. Natural Cycles is the only app of its kind to be available in Europe and the US for use as a contraceptive. The app can also be used to help plan a pregnancy when the time is right. Natural Cycles’ mission is to pioneer women’s health with research and passion, by empowering every woman with the knowledge she needs to be in charge of her health. Natural Cycles is headquartered in Sweden and has operations in the United States, Germany, Switzerland and the United Kingdom.

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  1. Wilcox AJ, Weinberg CR, Baird DD. (1995) Timing of Sexual Intercourse in Relation to Ovulation. New Eng J Med 333(23):1517-1521.
  2. Natural Cycles Survey conducted by ‘Research Now’. Understanding attitudes towards contraception in a cohort of women and healthcare professionals. August 2018. Women (n=4,023) and HCPs (n=499).
  3. Berglund Scherwitzl E, Lundberg O, Kopp Kallner H, Gemzell Danielsson K, Trussell J, Scherwitzl R. Perfect-use and typical-use Pearl Index of a contraceptive mobile app. Contraception. 2017;96(6):420-425.