The State of the Science of Natural Family Planning: A Report from NFP Scientists' Meeting Held in Orlando, FL, September 4, 2024

Michael D Manhart; Richard J Fehring

doi:10.1177/00243639251347842

Fertility Awareness · Effectiveness

The State of the Science of Natural Family Planning: A Report from NFP Scientists' Meeting Held in Orlando, FL, September 4, 2024

Manhart MD, Fehring RJ

Published August 2025 The Linacre Quarterly, 92(3), 336-349

DOI 10.1177/00243639251347842 PMID 40641837 PMC PMC12237956

RRM Academy Synopsis

Several NFP methods rank among the top in evidence quality, panel says

A panel of eighteen experts in natural family planning (NFP) felt that at least one available NFP method works well for most people. The 2024 meeting examined postpartum and perimenopausal use, app technology, and marital relations. In two systematic reviews, perfect-use unintended pregnancy rates ranged from 0 to 5 per 100 woman-years.

Key Findings

Two systematic reviews placed the Billings, Sympto Thermal, Marquette, Standard Days, and Two Day methods among their top-quality studies. Typical-use unintended pregnancy rates were <2 to 14 per 100-woman years.
With the Electronic Fertility Hormone Monitor marking the fertile window, pregnancy rates reached 80% after 6 cycles and 83% after 12. With cervical mucus monitoring they reached 48% and 73%.
Among 216 women retrospectively analyzed on an updated postpartum Marquette protocol, unintended pregnancy at 12 months was 3.5% with typical use and 1.5% with correct use.
Two apps have effectiveness evidence: DOT, with 5% typical-use unintended pregnancy, and Natural Cycles, with 8–9%. Both encourage barriers in the fertile window, so the panel does not class them as NFP.
Four population-based National Survey of Family Growth studies linked ever-use of NFP with reduced odds of divorce. The 2021 and 2023 studies also linked ever-use of common contraceptives with higher odds.

Interpretation

This report summarizes a one-day expert meeting in 2024. The panel drew on published studies, including two systematic reviews, cohort studies, and a few randomized trials. About 100 audience members joined the discussion, and panelists voted on research priorities, with the fifteen top-voted presented here. The divorce findings come from four population-based national surveys measuring NFP ever-use. The authors note that most effectiveness studies enrolled generally healthy women with regular cycles. The findings support larger studies on postpartum use, perimenopause, and women with identified health conditions.

RRM Context

Restorative reproductive medicine builds its evaluation on cycle charting. This report reviews the evidence for charting-based methods. The panel describes documented benefit from finding and treating underlying causes when couples struggle to conceive. The panel cites two reports that found benefit from restorative approaches in couples who had not conceived after several rounds of IVF. The panel suggests charting during treatment may sharpen diagnosis and help track each person's response.

Our editorial summary of this paper, not the article's abstract.

Abstract

A one-day meeting was held as a pre-conference to the Catholic Medical Association Annual Educational event in 2024. A panel of eighteen physicians, scientists, and researchers involved in NFP work was convened to review the available evidence in four topical areas: (i) evidence for effectiveness of NFP methods to postpone and achieve pregnancy, (ii) evidence for effectiveness in the postpartum and perimenopause transition periods, (iii) evaluate the current state of technology in NFP (specifically app and quantitative hormone monitoring), and (iv) evidence examining the impact of NFP on marital relations. In each topical area, the panel worked to reach a consensus opinion on the currently available evidence and identified priorities for further research. Results from these discussions and a set of priorities for further work are presented here.

Summary

An expert panel was convened to review the current evidence supporting use of NFP in various settings, utilization of new technology, and the impact of NFP on marital dynamics. Results from these discussions and a set of priorities for further work are presented here.

Topics

Fertility Awareness › Effectiveness › Typical and Perfect Use · Clinical Guidelines and Standards › Guideline Appraisal › Evidence Base and Strength of Recommendation · Postpartum › Return of Fertility › Postpartum Charting

Michael D Manhart, Richard J Fehring

Mike Manhart, M Manhart, Rick Fehring, Dick Fehring, Rich Fehring, R Fehring

PMID 40641837 40641837 DOI 10.1177/00243639251347842 10.1177/00243639251347842 Manhart et al. 2025, Manhart 2025

The State of the Science of Natural Family Planning: A Report from NFP Scientists' Meeting Held in Orlando, FL, September 4, 2024

Several NFP methods rank among the top in evidence quality, panel says

Key Findings

Interpretation

RRM Context

Abstract

Topics

By this author

Related research