Does Abstinence Work? Natural Methods Users and Consistency of Behavior

Ester L. Rizzi, Université Catholique de Louvain

The percentage of couples using natural family planning (NFP) who experienced an unintended pregnancy is 25% (Trussel, 2004). The high percentage of failures in preventing a pregnancy can depend on a misuse of the method, but also on the difficulty of observing the abstinence rule during the fertile days of the cycle. The aim of this paper is to assess consistency of behavior for users. A detailed typology of behaviors of ‘avoiders’, i.e. couples who try not to have intercourse in the fertile window, will be presented, together with an analysis of determinants of temporary interruption of an avoiding behavior. We will consider data on 1,074 couples and 10,508 menstrual cycles, for which acts of intercourse are recorded, coming from a Multinational Study on Daily Fecundability which involves 11 European NFP centers.