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Fertility Awareness Effectiveness

Calendar rhythm efficacy: a review

Kambic RT, Lamprecht V

Published June 1996 Advances in contraception : the official journal of the Society for the Advancement of Contraception
DOI 10.1007/bf01849633 PMID 8863907

Abstract

Objective

To estimate the unplanned pregnancy rate of calendar rhythm.

Design

Meta-analysis of eight studies of calendar rhythm published between 1940 and 1989.

Results

There exist few studies of the calendar rhythm method. Analysis of the best of these studies resulted in a conservative estimated Pearl rate of 18.5 +/- 1.8, and a less conservative estimate of 15.0 +/- 4.0, standardized to 12 months' observation; these results are in the range of other natural and barrier methods.

Discussion

We need properly done clinical trials of the calendar rhythm method to scientifically establish its effectiveness.

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By this author

Related research

Fertility Awareness › Effectiveness › Typical and Perfect Use · Contraception › Comparative Studies › Contraception Versus Fertility Awareness · Research Methods › Evidence Synthesis › Meta-Analysis
PMID 8863907 8863907 DOI 10.1007/bf01849633 10.1007/bf01849633 Kambic et al. 1996, Kambic 1996

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