When Theoretical Effectiveness to Avoid Pregnancy is Reduced

Barrier Methods

If a condom, spermicidal foam or gel, diaphragm, cervical cap, or other barrier methods are used for having intercourse on fertile days the couple is not longer using the Justisse Method to avoid pregnancy. They are using a barrier method with the awareness that they are using it on days the woman is fertile. Using days of fertility for intercourse with barriers may not protect you from pregnancy. The 99.6% effectiveness of the Justisse Method is based on abstinence from intercourse or any alternative sex on fertile days.

Note: The lubricative quality of the Type E cervical mucus causes a condom, diaphragm, or cervical cap to more easily slip off or slide out of place.

Alternative Sex on Fertile Days

Alternative sex practices used on fertile days may result in pregnancy. Alternative sex includes: withdrawal from intercourse just before the man ejaculates (comes); oral sex; mutual masturbation; anal intercourse; and penetration without ejaculation (coitus reservatus). Remember, the purpose of cervical mucus is to allow sperm to live and to transport it to the waiting ovum. Pre-ejaculatory fluid occurs when the man is aroused prior to ejaculation. When a woman is fertile, cervical mucus is present in her vagina as well as on surface of her vulva. A pregnancy can occur when alternative sex practices result in a man’s semen unintentionally mixing with a woman’s cervical mucus.

Some women and men feel ambiguous as to whether they want to achieve or avoid a pregnancy. "Taking a chance" seems okay for them. If you are very determined to avoid a pregnancy there should be no "taking chances". You will know each and every day whether or not you are fertile. Each and every day you choose based on your intention.

Intercourse or alternative sex on infertile days avoids pregnancy.

Intercourse or alternative sex on fertile days may achieve pregnancy.

Defining Days of Fertility and Infertility

The directions for defining days of fertility and infertility are outlined on the front of the Justisse Method Chart "Basic Charting Considerations". Follow these directions to help you accomplish your intentions. At the end of Chapter 7 you will find two sample charts entitled "Basic Charting". These charts demonstrate all the rules for defining fertile and infertile days, according to correct use of coloured stamps and observation notations. For easy reference all basic charting considerations are outlined in point form first. A detailed discussion for each point follows.