TO ACHIEVE A PREGNANCY: For couples of normal fertility, conception will occur 76% of the time in the first cycle of using a defined day of fertility.
TO AVOID A PREGNANCY: The method effectiveness is 99.5% in avoiding pregnancy when properly taught by a qualified teacher and then correctly applied. Journal of Reproductive Medicine, June 1998.
COUPLES WITH INFERTILITY: 20%-40% will achieve pregnancy with the CrMS only and up to 80% will conceive with additional cooperative medical assistance. http://naprotechnology.com/infertility.htm