Table 1.
Overview of fertility awareness-based methods (FABMs).
| Method | Biomarkers* | Identifies estimated day of ovulation | Published evidence to achieve pregnancy | Published evidence to prevent pregnancy | Considerations | Teacher training | Web-based or mobile apps† | Other methods using similar approach to identify fertile window†† |
|---|---|---|---|---|---|---|---|---|
| Billings Ovulation Method® | CF | Yes | Yes | Yes§ | Available through personal instruction§ | Yes | NFP Charting; Ovulation Mentor; Fertility Pinpoint | Fertility Education and Medical Management (FEMM); Family of the Americas |
| Creighton Model FertilityCare System™ | CF | Yes | Yes | Yes§ | Available through personal instruction§ | Yes | FertilityCare App | Justisse; NeoFertility |
| TwoDay® | CF | No | No | Yes | Not suitable for women with continuous vaginal discharge | Minimal | 2 Day Method | |
| Sympto-thermal, Sensiplan™|| | CF, BBT, CAL | Yes | Yes | Yes§ | Available through apps & personal instruction§ Requires adaptation for anovulation (no change in temperature) |
Variable | SymptoPro™; Kindara; Sympto; LilyPro; MyNFP LadyCycle; CyclePro Go | CCL-Couple to Couple League; SymptoPro™ |
| Natural Cycles | BBT (uLH) | Yes | Yes | Yes | Requires ovulatory cycles (temperature) | NA | Natural Cycles app is US FDA approved as contraceptive+ | |
| Marquette Method© | uLH, uE, CAL, (CF), (BBT) | Yes | Yes | Yes§ | Available through online and personal instruction§ Requires use of Clearblue® fertility monitor (cost) |
Yes | Web-based charting+ | |
| Dynamic Optimal Timing (DOT)™ | CAL | No | No | Yes | Cycles need to be 20–40 days long | NA | CLUE Birth Control app is US FDA approved as contraceptive+ | |
| Standard Days® | CAL | No | No | Yes | Cycles need to be 26–32 days long | Minimal | Cycle Beads | |
| Lactational Amenorrhea | Other | No | NA | Yes | Within first 6 months postpartum, no menstrual bleeding, totally breastfeeding | NA |
Biomarker abbreviations: CF, cervical fluid; BBT, basal body temperature; CAL, calendar calculations based on cycle length and/or prior days of ovulation; uLH, urine LH tests; uE, urinary estrogen metabolites. Parentheses indicate optional additional biomarker.
Apps or web applications were included if they followed the same guidelines for identifying the fertile window as the FABM method they represent (5), but only those apps marked with + been directly evaluated for pregnancy prevention.
These similar methods have no peer-reviewed evidence for effectiveness for pregnancy prevention among their own users.
In pregnancy prevention effectiveness studies of the Billings, Creighton, Sympto-Thermal Method and in most studies of the Marquette method, couples learned the method from a trained instructor.
Sensiplan—sympto-thermal method with the strongest evidence base, but with limited availability in the US.