by Elisa Burke
Background
Natural family planning (NFP) is a natural method of contraception in which varying markers of fertility are monitored, to work out the most fertile period of a woman’s cycle. On these days, intercourse can be avoided in order to prevent pregnancy (1).
It has long been advocated for by the Catholic Church, which opposes other methods of birth control. Sex, they believe, is for the purpose of procreation alone, and should solely occur within the context of marriage. Contraception is “intrinsically wrong”, according to Pope Paul VI’s teaching in 1968, and natural methods are the only acceptable way (2).
More recently, there has been a surge of popularity of natural methods of contraception, with social media promotion being a significant factor. The app ‘Natural Cycles’ is a tracking method for NFP, and the most famed brand associated with natural contraception. It has recently taken apps such as TikTok and Instagram by an advertising storm, with 25000 posts under the #naturalcycles tag on Instagram, and influencers such as Olivia Attwood and Ferne McCann being paid to promote it.
Many medical professionals have concerns surrounding this. Surely influencers, who (generally) do not have any kind of medical knowledge, and are being paid by a brand to promote a product, are not a trustworthy source for healthcare advice. So why are so many women following this method of contraception? How does it work? And, most importantly, does it actually work?
How does it work?
There is a range of methods which can be used within the category of NFP – the most classic being the rhythm method. This involves abstaining from sex around ovulation, which is usually on day 14 (3). Sex should be avoided on days 8-19, to account for early or late ovulation, and the 5 day viability of sperm in the female reproductive tract (4).
Another popular subtype of NFP is monitoring of basal body temperature (your temperature as soon as you wake up, before you get out of bed or eat or drink anything). This is expected to rise by 0.5-1 degree when ovulation occurs (3).
Tracking of cervical mucus can also be an indicator of fertility – this is clear and stretchy during ovulation (3).
Combining multiple NFP methods is done by some to increase effectiveness. The symptothermal method involves multiple NFP practices being done in combination, most commonly basal temperature and cervical mucus tracking (3).
Benefits
Although NFP is used as a contraceptive, its principles can also be applied in reverse to help aid conception, by tracking ovulation to time intercourse at the most fertile periods (1). This is seen as a perk of NFP – women learning more about their body’s fertility patterns can help them have greater understanding of their own health, which they may utilise in different ways to either increase or decrease chance of conception.
But by far the most appealing feature of NFP for many women is the lack of artificial hormones. Conventional methods of contraception, such as the pill and the implant, have nasty hormonal side effects which deter many users. These include headaches, mood swings and nausea, and even more scarily: increased risk of serious health conditions such as breast cancer and blood clots (5). With these terrifying side effects, it’s no wonder that so many women are being easily persuaded to switch to natural contraception. Zero side effects and supposed 98% effectiveness (6), according to Natural Cycles, sounds like the perfect solution to the contraceptive issues that many women have faced for their entire adult lives. So what’s the catch?
Effectiveness
With all methods of contraception, effectiveness is discussed in two components: perfect use and typical use. The NHS states that natural family planning has an effectiveness of 99% for perfect use (1). This is the same as the perfect use figure for the combined pill (5). However, natural methods of contraception are a lot harder to use perfectly than the pill, so there is greater scope for error.
Using the combined pill as an example, the simple requirement of the user is to remember to take it around the same time every day. With natural cycles, learning and following the method is a lot more complicated. Users must familiarise themselves with subtle changes in their body’s baseline, such as cervical mucus, which can be slight and subjective. This can take many months to properly learn, with the NHS recommending 3-6 months of preparation and learning before the method is relied on as the sole contraceptive (1). Once the method is perfected, it is still a significant time commitment, with daily monitoring and careful planning required.
The effectiveness of NFP can also be significantly affected by stress, illness and lifestyle changes. These all may impact the menstrual cycle, meaning that the timing of ovulation cannot be precisely tracked. For women who do not have regular cycles, the method is also much less likely to be effective (1).
Therefore, despite claims of high rates of effectiveness with perfect use, the figure for typical use is lower. The CDC states that the failure rate of natural family planning is as high as 24%, meaning that 24 pregnancies will result from 100 women using natural contraception methods in one year (7).
Drawbacks
Other issues of the method include lack of STI protection, and having to avoid sex for a large part of the monthly cycle. It is also not reliable for 2 complete cycles after use of the emergency contraceptive pill, due to the effect the pill has on ovulation (1).
The verdict
Overall, NFP may be an appealing option for those who don’t wish to use hormonal contraception. There are no side effects, and for Catholics it aligns with the Church’s teachings.
However, women should be wary of believing brands’ and influencers’ casual claims of 99% effectiveness. Although it can be effective when done correctly, the methods used are complex and subjective, and require learning, practise, and extensive monitoring. Efficacy can vary according to lifestyle changes and stress affecting ovulation, and it may not be accurate for those with irregular cycles. The rates of effectiveness with typical use are much lower than advertised by Natural Cycles, so it may not be a reliable method for those who require fail-safe protection from pregnancy.
Despite the wide choice of birth control options available now, it is disheartening that all of the options seem so unappealing. Why should women have to choose between tolerating the awful side effects of hormonal birth control, or risking the uncertainty that natural methods may pose?
Ultimately, it is up to women to make their own choices surrounding contraception. However, it is important that these choices are medically informed, with full knowledge of benefits and risks shared. If women are aware of the complexities and risks of natural family planning, then it be may suitable, and even a brilliant method of contraception for some. But there is, as with any contraception, a risk of pregnancy. This risk may be more significant than those who profit off Natural Cycles would have you believe. Moral of the story? Perhaps don’t trust an influencer to give you medical advice…
References
1. NHS. Natural family planning (fertility awareness). [internet]. 2021 [cited 2022 July 11]. Available from: https://www.nhs.uk/conditions/contraception/natural-family-planning/
2. Catholic Answers. Birth control. [internet]. 2004 [cited 2022 July 11]. Available from: https://www.catholic.com/tract/birth-control
3. WebMD. The natural family planning methods. [internet]. 2021 [cited 2022 July 11]. Available from: https://www.webmd.com/sex/birth-control/natural-family-planning-methods
4. Mayo Clinic. Healthy lifestyle: getting pregnant. [internet]. 2022 [cited 2022 July 11]. Available from: https://www.mayoclinic.org/healthy-lifestyle/getting-pregnant/expert-answers/pregnancy/faq-20058504
5. NHS. Combined pill. [internet]. 2020 [cited 2022 July 11]. Available from: https://www.nhs.uk/conditions/contraception/combined-contraceptive-pill/
6. Natural cycles. The science. [internet]. [date unknown] [cited 2022 July 11]. Available from: https://www.naturalcycles.com
7. CDC. Effectiveness of family planning methods. [internet]. [date unknown] [cited 2022 July 11]. Available from: https://www.cdc.gov/reproductivehealth/unintendedpregnancy/pdf/family-planning-methods-2014.pdf