HI Well come to HCM There are certain fact as long as the conception is concern, first this is physiological and natural phenomenon, depends upon certain conditions, like presence of ovum and sperm at the time of sexual intercourse, and fertilization of egg, implantation of fertilized egg in uterine cavity, if there is any obstruction in this process then conception may not happen, although yeast infection may not be the cause, some time even after everything are okay conception does not take place, hope this information helps, have a nice day.