In short Read article

Health apps for natural contraception: old wine in new bottles

Medical device not always reliable


Apps such as NaturalCycles® are being used by many women around the world as a natural, non-medical method of contraception. These apps are medical devices, which in principle have to meet the same requirements of effectiveness and safety as drugs. These should preferably be established by randomised studies. The NaturalCycles®-app might appear to be suitable for a selected group of highly motivated women to determine moments during a menstrual cycle when there is no risk of pregnancy. This does, however, require daily input of accurate data, like body temperature. There is no evidence from randomised studies that such an app is just as effective or ineffective as oral contraception, not even with flawless use. As long as this evidence is not available, care providers should not recommend this type of app as a contraceptive method.

  • Care providers need to be aware of the major limitations of using an app as a means of contraception.
  • The reliability of NaturalCycles® (a contraceptive app) is based on an algorithm to predict, with unknown uncertainty margin, the days on which a woman is not at risk of becoming pregnant.
  • Diagnostic apps predicting when a woman cannot become pregnant are not testable, as there is no gold standard reference test to determine ovulation.
  • Variations in menstrual cycles, uncertainty about the exact moment of ovulation, the importance of disciplined and accurate data input, and the need for supplemental contraception limit the general applicability of contraceptive apps.
  • No randomised studies into the effectiveness of contraceptive apps are known in which the pregnancy risk was directly compared with the risk when using hormonal contraception.

  1. Pagliari C. Commercial health apps: in the user's interest? BMJ. 2019;364:l1280.
  2. Tripp N, Hainey K, Liu A, Poulton A, Peek M, Kim J, et al. An emerging model of maternity care: smartphone, midwife, doctor? Women Birth. 2014;27(1):64-7.
  3. Händel P, Wahlström J. Digital contraceptives based on basal body temperature measurements. Biomed Signal Process Control. 2019;52:141-51.
  4. Su HW, Yi YC, Wei TY, Chang TC, Cheng CM. Detection of ovulation, a review of currently available methods. Bioeng Transl Med. 2017;2(3):238-46.
  5. Wilcox AJ, Dunson D, Baird DD. The timing of the "fertile window" in the menstrual cycle: day specific estimates from a prospective study. BMJ. 2000;321(7271):1259-62.
  6. Van Lunsen HW, Roumen FMJE. Anticonceptie en ongewenst zwangerschap.  Obstetrie en gynaecologie De voortplanting van de mens (Heineman MJ, Evers JLH, Massuger LFAG en Steegers EAP; zevende geheel herziene druk). Amsterdam: Reed Business 2012. p. 657-94.
  7. Peragallo Urrutia R, Polis CB, Jensen ET, Greene ME, Kennedy E, Stanford JB. Effectiveness of Fertility Awareness-Based Methods for Pregnancy Prevention: A Systematic Review. Obstet Gynecol. 2018;132(3):591-604.
  8. 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):420-5.
  9. Frank-Herrmann P, Stanford JB, Freundl G. Fertility awareness-based mobile application. Eur J Contracept Reprod Health Care. 2017;22(5):396-7.
  10. Helmerhorst FM, Nieuwhof MAE. Spiralen met levonorgestrel. Gebu. 2017;51(11):87-90.
  11. Sundaram A, Vaughan B, Kost K, Bankole A, Finer L, Singh S, et al. Contraceptive Failure in the United States: Estimates from the 2006-2010 National Survey of Family Growth. Perspect Sex Reprod Health. 2017;49(1):7-16.
  12. Collins WP. The evolution of reference methods to monitor ovulation. Am J Obstet Gynecol. 1991;165(6 Pt 2):1994-6.
  13. Pyper CM. Fertility awareness and natural family planning. Eur J Contracept Reprod Health Care. 1997;2(2):131-46.
  14. Grimes DA, Gallo MF, Grigorieva V, Nanda K, Schulz KF. Fertility awareness-based methods for contraception. Cochrane Database Syst Rev. 2004(4):CD004860.
  15. Thijssen A, Meier A, Panis K, Ombelet W. 'Fertility Awareness-Based Methods' and subfertility: a systematic review. Facts Views Vis Obgyn. 2014;6(3):113-23.
  16. Epstein DA, Lee NB, Kang JH, Agapie E, Schroeder J, Pina LR, et al. Examining Menstrual Tracking to Inform the Design of Personal Informatics Tools. Proc SIGCHI Conf Hum Factor Comput Syst. 2017;2017:6876-88.
  17. Starling MS, Kandel Z, Haile L, Simmons RG. User profile and preferences in fertility apps for preventing pregnancy: an exploratory pilot study. Mhealth. 2018;4:21.
  18. Gambier-Ross K, McLernon DJ, Morgan HM. A mixed methods exploratory study of women's relationships with and uses of fertility tracking apps. Digit Health. 2018;4:2055207618785077.

The literature refers to the Dutch text

Authors

  • Hajo I. Wildschut