Ovulation Method

A method of natural family planning in which days of possible fertility and peak fertility are recognized by the characteristics of cervical mucus. The couple will either refrain from sexual intercourse during this time to prevent pregnancy or have more frequent sexual intercourse to achieve pregnancy.
Found on http://www.pregnology.com/Pregnancy-dictionary/

ovulation method

cervical mucus method.
Found on http://www.encyclo.co.uk/local/21001
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