Objective: 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.Design: Current standards to evaluate contraceptive method effectiveness are reviewed. A framework for evaluating reports on NFP is presented.Results: 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.Discussion: Many factors influence NFP effectiveness, and these factors must be considered when evaluating published studies and designing future studies.

Most natural family planning studies in the literature are flawed in design and do not accurately calculate pregnancy rates, highlighting the need for improved study design and analysis.

Natural family planning effectiveness: evaluating published reports

Key Takeaway: Most natural family planning studies in the literature are flawed in design and do not accurately calculate pregnancy rates, highlighting the need for improved study design and analysis.