Sexuality and U

Health-Care Professionals

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Natural Family Planning


How They Work; Pros and Cons


Mechanism of Action

Abstinence from sexual intercourse during the female’s fertile time. This fertile period is calculated by using the calendar method, measuring the basal body temperature, observing changes in the vaginal mucus, maintaining a record to determine a predictable pattern.


Can be used at anytime when a woman is not in her fertile period. Requires continuous monitoring of menstrual cycles with accurate recording of the fertile window.

  1. No drug or device related side effects. 
  2. Enhances body awareness and understanding about natural fertility. 
Disadvantages/Side Effects
  1. Reliable only in well instructed and motivated women. 
  2. No protection from sexually transmitted infections. 
  3. Not reliable in women with irregular or unpredictable menstrual cycles. 
  4. Requires abstinence from sex for more than one week each month. 
  5. High rate of failure if improperly used. 

The Pearl index is 15-20 (failure rate for 100 women using this method for one year). Failure rate is highly dependent on body awareness and understanding of the fertility cycle.

Contraindications/Poor candidates
  1. Women unable to monitor their cycles, keep accurate records and/or abstain from sex for several days each month. 
  2. Women unable to accept the significant possibility of failure of this method.

None required. The couple would likely benefit from a repeat visit following a few cycles of charting to review the method and individualize the concept of fertile days.