What you need to know Fertility awareness based methods of contraception are increasingly being used for pregnancy prevention.1 In the US, the proportion of contraceptive users who choose such methods has grown from 1% in 2008 to approximately 3% in 2014.12 Relative to other methods of pregnancy prevention, however, substantial misinformation exists around fertility awareness based methods of contraception, particularly about the effectiveness of specific methods and how to use them. Providers who offer family planning counselling can promote correct and consistent use of the chosen method by helping people find a method that best fits their individual lifestyle, preferences, and goals.3 This article aims to help clinicians counsel people about fertility awareness based methods for pregnancy prevention by explaining the different methods, the evidence base for their effectiveness, and practical considerations for use. Fertility awareness based methods are devised on the premise that sexual intercourse can only lead to pregnancy during approximately 6-9 days of the menstrual cycle, commonly referred to as the “fertile window” (or fecund window, box 1).5 …
fertility awareness based methods pregnancy prevention effectiveness, natural family planning contraceptive counseling clinical guidance, fertile window identification pregnancy prevention methods, fertility awareness methods correct consistent use effectiveness, Urrutia Polis fertility awareness contraception BMJ, FABMs contraceptive effectiveness comparison family planning, fertility awareness based methods misinformation clinician education, menstrual cycle fertile window contraception natural methods, symptom-based calendar-based fertility awareness methods review, family planning counseling fertility awareness patient preferences
PMID 31296535 31296535 DOI 10.1136/bmj.l4245 10.1136/bmj.l4245 Urrutia et al. 2019, Urrutia 2019
Cite this article
Urrutia, R. P., & Polis, C. B. (2019). Fertility awareness based methods for pregnancy prevention. BMJ (Clinical research ed.), 366, l4245. https://doi.org/10.1136/bmj.l4245
Urrutia RP, Polis CB. Fertility awareness based methods for pregnancy prevention. BMJ. 2019;366:l4245. doi:10.1136/bmj.l4245
Urrutia, R. P., and C. B. Polis. "Fertility awareness based methods for pregnancy prevention." BMJ (Clinical research ed.), vol. 366, 2019, pp. l4245.
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Open Access
Damba-Cunningham E et al., 2025·J Restorative Reprod Med
Fertility awareness-based methods (FABM) of family planning have increased in popularity in recent years. The effectiveness of various methods can vary substantially and can be user dependent. For various reasons, there is a bias in OBGYN physicians against the use of FABMs for family planning. However, once educated about the methods of FABMs, this bias improves. There is limited regarding the education dedicated to FABM use in residency. We hypothesized that the residency education obtained regarding FABMs would be insufficient in preparing resident OBGYNs in effectively counseling patients regarding FABMs. a 16-question survey was created via SurveyMonkey and was sent to all ACGME accredited OBGYN residency programs for distribution to current residents. The survey was administered from October 2023 to December 2023. 125 responses were collected. Less than 40% of residents received formal training in regards to FABMs. Respondents indicated they felt most comfortable describing the calendar method to patients (68% respondents agree or strongly agree when queried if they could describe the method). 79.5% of respondents could not describe mucus-only, hormone monitoring, or sympto-thermal methods of family planning. When questioned if they were prepared to counsel postpartum patients who refused contraception regarding FABM, 58% of respondents indicated they could not assist their patients. Despite increased use in recent years and multiple options for FABM use, resident education in the application and use of FABMs is lacking. Additionally, residents indicated they are most familiar with the least effective methods (calendar method) which would likely be a significant detriment to their patients.
Calendar-based methods are not usually considered effective or useful methods of family planning among health professionals. However, new "high-" and "low"-tech calendar methods have been developed, which are easy to teach, to use, and may be useful in helping couples avoid pregnancy. The low-tech models are based on a fixed-day calendar system. The high-tech models are based on monitoring urinary metabolites of female reproductive hormones. Both systems have high levels of satisfaction. This article describes these new models of family planning and the research on their effectiveness. The author proposes a new algorithm for determining the fertile phase of the menstrual cycle for either achieving or avoiding pregnancy.
A significant number of women worldwide use periodic abstinence as their method of family planning. Many of them use some type of calendar-based approach to determine when they should abstain from unprotected intercourse to avoid pregnancy; yet they often lack correct knowledge of when during their menstrual cycle they are most likely to become pregnant. A simple method of natural family planning (NFP) based on a fixed formula to define the fertile window could be useful to these women. This article reports the results of an analysis of the application of a fixed formula to define the fertile window. A large existing data set from a World Health Organization study of the Ovulation Method was used to estimate the theoretical probability of pregnancy using this formula. Information about the variable probability of pregnancy on different cycle days relative to ovulation also was considered in the analysis. Results suggest that a fixed formula in which days 8-19 of the menstrual cycle are considered to be the fertile window would provide the appropriate basis of a simple, effective, family planning method.
5 major criteria are used to evaluate family planning efficacy, both theoretical and practical; acceptability as measured by continuation of use; safety; reversibility; and cost, including the cost of treatment, follow-up, and screening for contraindications. Traditional family planning methods are mostly based on periodic abstinence during the presumed fertile period. The calendar, temperature, Billings or cervical mucus, and symptothermal methods are based on observation of different symptoms of ovulation and fertility. Their advantages are that they do not require intervention by health personnel, their costs of use are nil, and they are morally acceptable to some couples. Their efficacy is lower than that of other methods and they should be viewed as methods to space rather than limit births. The withdrawal method, also less effective, requires active cooperation by the male partner. Among mechanical methods, the use of condoms has increased recently because of the protection they offer against HIV infection and other sexually transmitted diseases. Their efficacy depends on correct use, regular use, and the quality of the condom. The Pearl index varies from 93099 per 100 woman-years. The diaphragm must be individually measured and should be used with spermicides. The Pearl index ranges from 85095 per 100 woman-years. Spermicides, generally either nonoxynol-9 or benzalkonium chloride, are surfactants that have a Pearl index of 83-97 per 100 woman-years. They are available as creams, jellies, foams, suppositories, tablets, or impregnated sponges. Most failures appear due to errors of utilization. The mechanism of action of the IUD is imperfectly understood, but it is known to prevent nidation of the fertilized egg. Copper devised have higher rates of efficacy and tolerance. Pearl indices range from 95-99.5. Contraindications include genital infection, uterine anomalies, valvular cardiopathy, and coagulation problems. The IUD is relatively contraindicated if there is history of ectopic pregnancy or upper genital tract infections. The combined oral contraceptive is the most widely utilized method in France. The Pearl index is nearly 100 in the absence of forgetting, vomiting, or drug interactions. The contraindications are basically those of estrogens: history of thrombosis, prolonged bedrest, hypertension, hyperlipidemia, hepatic disorders, hormonodependent cancers, or smoking after age 35. Progestin-only methods are available in 3 forms: low-dose pills which must be taken at the same time each day, higher-dosed progestins taken for 20 days each month, and injectable progestins providing contraception for 8-12 weeks. Postcoital contraception using OCs or IUDs is possible but not well known among women or physicians. The Neuwirth law authorizing use of contraception in France was passed in 1967. Amendments in 1974 improved access and provided for reimbursement for some methods, but some newer forms are not reimbursed.