Natural family planning
It is now well accepted that a woman can conceive from an act of intercourse for a maximum of only about 7 days of her menstrual cycle. The reliability of natural family planning depends on identifyin...
Advances in Contraception : the Official Journal of the Society for the Advancement of Contraception, 13(2-3), 155-165
To equip the reader with the tools necessary to evaluate studies of natural family planning (NFP) effectiveness found in the literature and to make recommendations for future NFP effectiveness studies.
Current standards to evaluate contraceptive method effectiveness are reviewed. A framework for evaluating reports on NFP is presented.
Most NFP studies found in the literature are flawed in design and do not calculate pregnancy rates correctly. The results from the few well-designed studies are presented.
Many factors influence NFP effectiveness, and these factors must be considered when evaluating published studies and designing future studies.
Lamprecht, V., & Trussell, J. (1997). Natural family planning effectiveness: evaluating published reports. *Advances in contraception : the official journal of the Society for the Advancement of Contraception*, *13*(2-3), 155-165. https://doi.org/10.1023/a:1006595703472
Lamprecht V, Trussell J. Natural family planning effectiveness: evaluating published reports. Adv Contracept. 1997;13(2-3):155-165. doi:10.1023/a:1006595703472
Lamprecht, V., and J. Trussell. "Natural family planning effectiveness: evaluating published reports." *Advances in contraception : the official journal of the Society for the Advancement of Contraception*, vol. 13, no. 2-3, 1997, pp. 155-165.