Natural Methods

Natural Methods

Natural contraceptive methods, also called fertility awareness-based methods (FABMs), rely on the identification of the fertile window in the menstrual cycle, so as to avoid sexual intercourse during the days when conception is most likely. Unlike medical or mechanical contraceptives, these methods do not involve external hormones or devices.

Types of natural methods

1. Calendar (Rhythm) Method:

Estimates the fertile period based on the length of previous menstrual cycles. Works on the principle that ovulation occurs 14 days before the next period and chances of pregnancy is highest during the days before and after ovulation known as the fertile window. Fertile window: lasts from days 10 to day 19 (for a 28–32 day cycle) Avoid intercourse during fertile days.

Efficacy:

1. Typical use: ~76%

2. Perfect use: ~91%

Limitations: Requires regular cycles, less effective if cycles are variable.

1. Basal Body Temperature (BBT) Method

Monitors resting body temperature every morning before rising. A sustained rise of ~0.3–0.5°C indicates ovulation has occurred and this happens due to the rise in luteinizing hormone and progesterone.

Fertile period: 2–3 days before the temperature rise

Abstinence advised until 3 days after temperature rise

Efficacy:

Typical use: ~76–80%

Perfect use: ~98%

Limitations: Affected by illness, poor sleep, alcohol, stress and also ambient temperature

Requires consistent monitoring.

1. Cervical Mucus (Billings Ovulation) Method

Observes changes in cervical mucus throughout the cycle. Clear, stretchy, "egg white" mucus signals peak fertility (ovulation).

Fertile window: Begins when mucus becomes watery/slippery, ends 4 days after peak

Avoid intercourse when this change is noted

Efficacy:

Typical use: ~75–88%

Perfect use: ~95–97%

Limitations: Needs high motivation, accurate interpretation, and daily monitoring.

Not very practical

1. Symptothermal Method

Combines multiple indicators: BBT, cervical mucus, and sometimes ovulation pain or cervix position.

Efficacy:

Typical use: ~80–87%

Advantages:

Higher accuracy due to combined methods.

Better adaptability to cycle variation as multiple methods are used.

1. Withdrawal Method (Coitus Interruptus)

The male partner withdraws the penis before ejaculation, aiming to prevent sperm from entering the vagina.

Efficacy:

Typical use: ~78%

Limitations:

Risk of pre-ejaculate containing sperm

High user dependency

High motivation for use of method

1. Lactational Amenorrhea Method (LAM)

Mechanism: Relies on exclusive breastfeeding, which suppresses the GnRH–LH–FSH axis, inhibiting ovulation.

Criteria for effectiveness:

Infant <6 months

Exclusive breastfeeding (no supplemental feeds)

Amenorrhea (no return of menstruation)

Efficacy:

~98% (first 6 months postpartum if criteria met)

Conclusion

Natural contraceptive methods are viable for motivated individuals seeking hormone- or device-free options. While they offer health and cost advantages, they demand education, discipline, and cooperation from both partners. With correct use, certain FABMs can approach the efficacy of modern contraceptives, but their effectiveness significantly declines with typical user error.

References:

1. Duane M, Stanford JB, Porucznik CA, Vigil P. Fertility awareness-based methods for women's health and family planning. Frontiers in Medicine. 2022 May 24;9:858977.

1. Grimes DA, Gallo MF, Halpern V, Nanda K, Schulz KF, Lopez LM. Fertility awareness‐based methods for contraception. Cochrane Database of Systematic Reviews. 2004(4).