Sexual relations are open to you every other evening, so that you learn to recognize the difference between seminal fluid and the beginning of the fertile phase when cervical mucus begins to flow.
The reason for this rule is that you need to be on your feet for a few hours in case the fertile mucus, which originates at the cervix, begins to flow down through the vagina to the vulva. By abstaining all day, you can be certain, by the end of the day, that no mucus was present or whether a sensation of wetness was felt. Sexual relations every day before cervical mucus may lead to confusion and to pregnancy.
