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Merck Manual
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Health Topics & Chapters
Comparison of Fertility Awareness‒Based Methods of Contraception

Comparison of Fertility Awareness‒Based Methods of Contraception

Method

Percentage of Women Who Become Pregnant During First Year of Use With Perfect Use

Percentage of Women Who Become Pregnant During First Year of Use With Typical Use

Calendar method

5%

12%

Mucus method

4%

14%

Symptothermal

< 1%

2%

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