Randomized comparison of two Internet-supported fertility-awareness-based methods of family planning

Contraception. 2013 Jul;88(1):24-30. doi: 10.1016/j.contraception.2012.10.010. Epub 2012 Nov 12.


Background: The aim was to compare the efficacy and acceptability of two Internet-supported fertility-awareness-based methods of family planning.

Study design: Six hundred and sixty-seven women and their male partners were randomized into either an electronic hormonal fertility monitor (EHFM) group or a cervical mucus monitoring (CMM) group. Both groups utilized a Web site with instructions, charts and support. Acceptability was assessed online at 1, 3 and 6 months. Pregnancy rates were determined by survival analysis.

Results: The EHFM participants (N=197) had a total pregnancy rate of 7 per 100 users over 12 months of use compared with 18.5 for the CMM group (N=164). The log rank survival test showed a significant difference (p<.01) in survival functions. Mean acceptability for both groups increased significantly over time (p<.0001). Continuation rates at 12 months were 40.6% for the monitor group and 36.6% for the mucus group.

Conclusion: In comparison with the CMM, the EHFM method of family planning was more effective. All users had an increase in acceptability over time. Results are tempered by the high dropout rate.

Trial registration: ClinicalTrials.gov NCT00843336.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Algorithms
  • Cervix Mucus / metabolism
  • Estrone / analogs & derivatives
  • Estrone / urine
  • Family Characteristics
  • Female
  • Humans
  • Intention to Treat Analysis
  • Internet*
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Natural Family Planning Methods*
  • Patient Acceptance of Health Care
  • Patient Dropouts
  • Patient Education as Topic*
  • Pregnancy
  • Pregnancy Rate
  • Self Care*
  • Young Adult


  • estrone-3-glucuronide
  • Estrone

Associated data

  • ClinicalTrials.gov/NCT00843336