The information and questions provided below are designed to support your counseling so that you and your patients can make informed choices.
Natural Cycles may be suitable for women who are looking for a natural method of contraception and have a lifestyle that enables them to take their temperature first thing most mornings.
Evidence shows that a woman who, following consultation with her HCP, has actively chosen a method of contraception and is satisfied with it, is more likely to use it consistently and correctly. On the other hand, women using a method which is not in line with their personal preferences may be less likely to adhere to, or continue with that method, which could increase the risk of an unplanned pregnancy.¹This is why contraceptive choice is so important.
More red days in the beginning
The algorithm adapts to every woman’s unique cycle pattern by learning over time as she adds more data. The number of green days increases accordingly, therefore, a woman who inputs temperature readings regularly and often (at least 5 times a week), has a regular cycle and a non-deviating temperature is likely to receive more green days. The algorithm has been intricately designed to account for sperm survival, variation in cycle length, ovulation day, temperature fluctuations and the length of the follicular and luteal phase, and is sensitive to subtle patterns in a woman’s cycle.
In light of this information, it is necessary to inform patients that patience is required over the first few weeks, and that it may take several cycles of consistent measuring and entering data for the app to become familiar with a woman’s individual cycle and detect ovulation. As such, it is normal that more red days are given initially.
Women discontinuing hormonal contraception
For women who have recently stopped using hormonal contraception, it is not unusual to experience anovulatory cycles for a couple of months.
A woman can start using Natural Cycles the day after she discontinues using hormonal contraception. Until her first ovulation is detected, she should expect many red days as a Prevent user.
IMPORTANT: women should not measure while still on hormonal contraception since the hormones inhibit ovulation and also affect temperature and cycles. Therefore a combination of hormonal contraception and Natural Cycles is not possible.
Women with irregular cycles
Small irregularities are quite common, especially if a woman has recently stopped using hormonal contraception. The Natural Cycles algorithm takes factors such as cycle regularity and temperature fluctuations into account when analysing individual cycles and calculating fertility status for the day.
Natural Cycles may be less suitable as a contraceptive if a woman’s cycle is very irregular, since she will get more red days, yet by tracking her cycle, she will get to know how her own individual cycle.
|Contraceptive Method||% of women experiencing |
an unintended pregnancy
within the first year of use
|Potential side effects|
|Hormonal IUS²||0.2||No||No||Yes||Yes, hormone-related|
|Traditional³ fertility |
|Combined pill and |
Natural Cycles’ effectiveness is based on clinical research, please see the results of our peer-reviewed publications.