Natural family planning effectiveness in Belgium

The aim of the study was to check, in a European environment, the practical efficiency and the acceptability of a recent natural family planning (NFP) method. This method includes a double check to detect the beginning as well as the end of the fertile phase of the menstrual cycle. Up to now, 71 women of reproductive age have been registered. They agreed to provide their symptothermal charts and related information. Average age is 32 years. Average fertility is 2 children/woman. Fifty-nine percent of the participants have a professional occupation. The same percentages are found in those accepting a contraceptive method (oral contraceptives or intrauterine devices). Until today 1240 cycles (103 women-years) of experience have been gathered. The average participation was 17.5 cycles/woman. No method failure has been reported. One unintended pregnancy due to unprotected sexual intercourse during the fertile phase occurred (user failure). Overall Pearl Index (PI) was 0.96. In 84% of the cycles, no protected intercourse was reported (NFP only). According to PI, practical efficiency of the NFP method analyzed was 1.31. Sexual abstinence during the fertile phase was found in 71.4% of the cycles.