Following menstruation there will often be a number of days when you may feel dry and see no discharge. This is called the Basic Infertile Pattern (BIP). We know from the work of the scientists that the hormone levels are low at this time and the cervix is blocked preventing entry of sperm. Therefore as a couple you are infertile for a variable number of days.

In the other common type of Basic Infertile Pattern there are no days without discharge after menstruation.  You may feel something at the vulva.  This sensation and any mucus that you see will be unchanging day after day.  Again the hormone levels are low and the cervix is blocked, resulting in infertility throughout this time.

This pattern of infertility can continue for a few days or for weeks or even months when ovulation is delayed (for example while breastfeeding). Your Billings Ovulation Method™ tutor will help you interpret your Basic Infertile Pattern so that you can apply the Early Day Rules with confidence.