IMPORTANT: If a woman has a vaginal infection or another condition that changes cervical mucus, this method may be difficult to use.

Check cervical secretions daily
  • The woman checks every day for any cervical secretions on fingers, underwear, or tissue paper or by sensation in or around the vagina.
Avoid unprotected sex on days of heavy monthly bleeding
  • Ovulation might occur early in the cycle, during the last days of monthly bleeding. Heavy bleeding could make mucus difficult to observe.
Resume unprotected sex until secretions begin
  • Between the end of monthly bleeding and the start of secretions, the couple can have unprotected sex, but not on 2 days in a row. (Avoiding sex on the second day allows time for semen to disappear and for cervical mucus to be observed.)
  • It is recommended that they have sex in the evenings, after the woman has been in an upright position for at least a few hours and has been able to check for cervical mucus.
Avoid unprotected sex when secretions begin and until 4 days after "peak day"
  • As soon as she notices any secretions, she considers herself fertile and avoids unprotected sex.Arrow pointing to cervical mucus secretions
  • She continues to check her cervical secretions each day. The secretions have a “peak day”—the last day that they are clear, slippery, stretchy, and wet. She will know this has passed when, on the next day, her secretions are sticky or dry, or she has no secretions at all. She continues to consider herself fertile for 3 days after that peak day and avoids unprotected sex.
Resume unprotected sex
  • The couple can have unprotected sex on the 4th day after her peak day and until her next monthly bleeding begins.