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Randomized Comparison of Two Internet-Supported Methods of Natural Family Planning

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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 (pb.01) in survival functions. Mean acceptability for both groups increased significantly over time (pb.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.

Document Rights and Citation of Original

Accepted version. Contraception, Vol. 88, No. 1 (July 2013): 24-30. DOI.

© 2013 Elsevier. Used with permission.

NOTICE: this is the author’s version of a work that was accepted for publication in Contraception. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Contraception, VOL 88, ISSUE 1, (July 2013) DOI.

Additional Files

data_nfp_005.pdf (204 kB)
Randomized Comparison Figure 1

data_nfp_006.pdf (289 kB)
Randomized Comparison Figure 2

data_nfp_007.pdf (163 kB)
Randomized Comparison Table 1

data_nfp_008.pdf (8 kB)
Randomized Comparison Table 2