title: Fertility awareness-based methods of family planning: predictors of correct use.
abstract: BACKGROUND
  Fertility awareness-based methods of family planning help women identify the days of the menstrual cycle when they are most likely to become pregnant. To prevent pregnancy, women avoid unprotected intercourse on these days. Efficacy of these methods may be improved if the users most likely to engage in unprotected intercourse on fertile days can be identified and counseled.
  
  
  METHODS
  Quantitative and qualitative data from efficacy studies of the Standard Days Method and the TwoDay Method of family planning, in which 928 women each contributed up to 13 cycles of method use, were examined. Multinomial logit analysis was used to compare characteristics of women who occasionally had unprotected intercourse on fertile days with those who consistently used their method correctly. The reasons participants gave for having unprotected intercourse on fertile days were also examined.
  
  
  RESULTS
  Only 23% of women had unprotected intercourse on their fertile days in one or more of the cycles they contributed to the study. The method and study site appear to have the most significant effect on correct use. Earning an income was associated with increased odds of unprotected intercourse on fertile days; higher quality of housing was associated with decreased odds. The results confirm the importance of partner cooperation for correct method use.
  
  
  CONCLUSIONS
  There was no clear profile of clients for whom these family planning methods would be inappropriate. However, programs offering these methods may help couples overcome potential difficulties in correct method use by including male partners and encouraging their participation in counseling sessions.
authors.affiliation: Institute for Reproductive Health, Georgetown University, Washington, DC, USA. irh@georgetown.edu
authors.forename: Irit
authors.initials: I
authors.lastname: Sinai
authors.forename: Rebecka
authors.initials: R
authors.lastname: Lundgren
authors.forename: Marcos
authors.initials: M
authors.lastname: Arévalo
authors.forename: Victoria
authors.initials: V
authors.lastname: Jennings
mesh_terms: D000328:Adult; D003268:Contraception Behavior; D005260:Female; D005298:Fertility; D006801:Humans; D007843:Latin America; D008297:Male; D012252:Natural Family Planning Methods / Q000706:statistics & numerical data*; D010679:Philippines; D012746:Sexual Abstinence; D012725:Sexual Behavior; D012959:Socioeconomic Factors