What is the effectiveness of menstrual cycle tracking for contraception in sexually active females?

From the Guidelines

Menstrual cycle tracking is not recommended as a primary method of contraception due to its relatively high failure rates, with a typical use failure rate of 24% as reported in the 2013 study by the U.S. selected practice recommendations for contraceptive use 1. When considering the effectiveness of menstrual cycle tracking for contraception, it's essential to differentiate between perfect use and typical use. Perfect use of fertility awareness-based methods can have a failure rate as low as 0.4% for the symptothermal method, as indicated in the study 1. However, typical use, which is more representative of real-world scenarios, shows significantly higher failure rates, ranging from 12% to 24% for different fertility awareness-based methods 1.

Key Considerations

• The effectiveness of menstrual cycle tracking heavily depends on the user's ability to perfectly track their cycle and fertility signs, which can be challenging for many women.
• The method requires a significant commitment to daily monitoring and record-keeping, making it less suitable for women with busy lifestyles or those who prefer more straightforward contraceptive methods.
• Women with irregular cycles, recent childbirth, breastfeeding, approaching menopause, or certain medical conditions may find menstrual cycle tracking less reliable due to variations in their menstrual cycles and fertility signs.

Comparison with Other Contraceptive Methods

• Hormonal contraceptives, such as the combined pill and progestin-only pill, have a typical use failure rate of 9% and a perfect use failure rate of 0.3% 1.
• Intrauterine devices (IUDs) have a failure rate of less than 1%, making them one of the most effective forms of contraception 1.

Recommendations for Use

Given the relatively high failure rates associated with menstrual cycle tracking, it is crucial for women to consider their lifestyle, menstrual regularity, and the level of commitment they can dedicate to tracking their fertility signs before choosing this method. For most women, especially those seeking a highly effective method of contraception, alternatives like hormonal contraceptives or IUDs are recommended due to their significantly lower failure rates 1.

From the Research

Effectiveness of Menstrual Cycle Tracking for Contraception

The effectiveness of menstrual cycle tracking for contraception in sexually active females has been studied in various research papers.

• A study published in 2022 2 discusses the use of fertility awareness-based methods (FABMs) for family planning, which involve tracking physical signs such as cervical fluid secretions and basal body temperature to identify ovulation and the fertile window.
• Another study from 2001 3 validates the theoretical effectiveness of the TwoDay method, a simple approach to identify the fertile window by tracking cervical secretions.
• A 2021 study 4 assesses the effectiveness of the Natural Cycles app, a digital fertility awareness-based method, and reports a 13-cycle cumulative pregnancy probability of 7.2% and a 1-year typical use pearl index of 6.2.
• The effectiveness of the symptothermal method (STM), which uses temperature and cervical secretions observation, is reported in a 2007 study 5, with a pregnancy rate of 0.6 per 100 women and per 13 cycles when there is no unprotected intercourse in the fertile time.
• A 2014 study 6 examines the efficacy of natural family planning (NFP) methods among perimenopause age women and reports a typical use pregnancy rate of six per 100 women over 12 months.

Factors Affecting Effectiveness

The effectiveness of menstrual cycle tracking for contraception can be influenced by various factors, including:

• Correct use and adherence to the method 5
• Accurate tracking of physical signs and symptoms 2, 3
• Motivation to limit family size 6
• Diminished fertility with age 6
• Quality of instruction and guidance 2, 5

Comparison of Methods

Different studies have reported varying effectiveness rates for different menstrual cycle tracking methods, including:

• FABMs: highly effective when taught by a trained instructor 2
• TwoDay method: highly effective in identifying the fertile window 3
• Natural Cycles app: effective with a typical use pearl index of 6.2 4
• STM: highly effective with a pregnancy rate of 0.6 per 100 women and per 13 cycles 5
• NFP methods: effective among perimenopause age women with correct use and adequate instructions 6