title: [The 1st phase of a prospective study of the effectiveness of natural family planning conducted in French-speaking Belgium].
abstract: The aim of this pilot-study is to check the practical efficiency and the acceptability of a recent NFP method in Western Europe.
  
  
  METHODS
  In a first stage, 58 participants, aged 18 to 49, provided 940 cycles (78 woman-years) being with an average of 16 cycles each, all well-documented (sympto-thermal chart and supporting card). The average age of the women was 32 years. 53% of them have chosen NFP after giving up another contraceptive method. The applied NFP method uses a double check to accurately define the beginning as well as the end of the fertile phase of the menstrual cycle. The indicators of the beginning of the fertile phase were: the first sign of cervical mucus and a calendar calculation. The indicators of the end of the fertile period were: the third morning of high temperature and the evening of the fourth day after the peak mucus or the peak cervix. Four participants out of five regularly uses the cervix index.
  
  
  RESULTS
  No method failure was seen. One unplanned pregnancy (user failure) was recorded. Pearl-Index (practical effectiveness of the method) was: 1.75. Pure NFP (i.e. no additional contraceptive means during the fertile phase) was applied in 85% of the cycles. Moreover unprotected sexual intercourse during the fertile phase occurred in 17% of the cycles. So in 71% of the cycles, couples had accepted periodic abstinence.
  
  
  CONCLUSIONS
  After more than 78 years of use, it appears that an accurate and thoroughly taught sympto-thermal method of NFP shows a use-effectiveness which can be compared to that of the up-to-date contraceptive methods. The acceptance of the method proved to be excellent. The acceptability turns out to be very good.
authors.affiliation: Ancienne Externe des Hôpitaux de Paris.
authors.forename: M A
authors.initials: MA
authors.lastname: De Leizaola
mesh_terms: D000293:Adolescent; D000328:Adult; D001530:Belgium; D001831:Body Temperature / Q000502:physiology; D002582:Cervix Mucus / Q000502:physiology; D003075:Coitus; D003267:Contraception / Q000379:methods*; D005193:Family Planning Services; D005260:Female; D005298:Fertility / Q000502:physiology; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology; D008875:Middle Aged; D017060:Patient Satisfaction; D010865:Pilot Projects; D011247:Pregnancy; D011446:Prospective Studies; D012725:Sexual Behavior
vernacular_title: Première phase d'une étude prospective d'efficacité du planning familial naturel réalisée en Belgique francophone.